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We outline a simple routine to correct for non-uniformities in the energy dispersion of a post-column electron energy-loss spectrometer for use in scanning transmission electron microscopy. We directly measure the dispersion and its variations by sweeping a spectral feature across the full camera to produce a calibration that can be used to linearize datasets post-acquisition, without the need for reference materials. The improvements are illustrated using core excitation electron energy-loss spectroscopy (EELS) spectra collected from NiO and diamond samples. The calibration is rapid and will be of use in all EELS analysis, particularly in assessments of the chemical states of materials via the chemical shift of core-loss excitations.

High quality ceramics of Ba((Co 0.7 Zn 0.3 ) 1/3 Nb 2/3 )O 3 (BCZN), Ba(Mg 1/3 Nb 2/3 )O 3 (BMN) and Ba(Mg 1/3 Ta 2/3 )O 3 (BMT) were prepared by the mixed oxide route using sintering temperatures up to 1620 °C. Products with a high degree of cation ordering exhibited dielectric Q × f values from 83,000 GHz (BCZN) to 360,000 GHz (BMT). High Resolution TEM and aberration-corrected scanning transmission electron microscopy (STEM) revealed ordering domains and type I, II and III boundary structures. High-Angle Angular Dark Field (HAADF) STEM images provided direct evidence of 1:2 ordering and stacking sequences, and the presence of disordered regions within domain boundaries. The exceptionally high Q × f values for BMT are associated with a high degree of B-site ordering and the removal of domain boundaries in large, single domain grains. The catastrophic degradation of Q × f values in BMN after prolonged sintering is associated with formation of a lossy ferroelectric secondary phase (Ba 3 Nb 2 O 8 ), and changes to composition and stoichiometry of BMN grains.

With advancements in aberration-corrected electron optics, the resolution in scanning transmission electron microscopy (STEM) has been significantly improved. More importantly, the reduction of the probe size and the increase of the probe current density enable the acquisition of elemental maps at the atomic scale in a fast manner using both EELS and EDS. With the latest generations of EELS spectrometers, atomic resolution compositional and chemical maps allow interfaces, oxidation state, and even single atoms to be examined with increasing detail. These improvements have also enabled elemental and chemical maps to be acquired rapidly using both low- and high-energy edges from elements across the periodic table, including heavy atoms such Au or Pt. On the EDS side, the introduction of large-area silicon drift detectors (SDD) has allowed these high-beam-current sources to be fully utilized. Improved detector area and support for higher count rates, compared to the previous generation of EDS detectors, allows the acquisition of EDS intensity maps from most types of material in the STEM, even for moderately thin samples. For the case of light elements, the reduced detector dead layer of SDD-based systems partially overcomes the very low florescence yield typical of low-energy X-ray lines. Also as reported in, atomic-level X-ray maps using fast detectors and bright sources can now be collected under some conditions. Because EDS and EELS provide complementary information about the sample, and are both generated with the electron beam, it would be wasteful to not acquire both datasets with every sample run.

Crystal surfaces provide physical interfaces between the geosphere and biosphere. It follows that the arrangement of atoms at the surfaces of crystals profoundly influences biological components at many levels, from cells through biopolymers to single organic molecules. Many studies have focused on the crystal-molecule interface in water using large, flat single crystals. However, little is known about atomic-scale surface structures of the nanometer- to micrometer-sized crystals of simple metal oxides typically used in batch adsorption experiments under conditions relevant to biogeochemistry and the origins of life. Here, we present atomic-resolution microscopy data with unprecedented detail of the circumferences of nanosized rutile (α-TiO2) crystals previously used in studies of the adsorption of protons, cations, and amino acids. The data suggest that one-third of the {110} faces, the largest faces on individual crystals, consist of steps at the atomic scale. The steps have the orientation to provide undercoordinated Ti atoms of the type and abundance for adsorption of amino acids as inferred from previous surface complexation modeling of batch adsorption data. A remarkably uniform pattern of step proportions emerges: the step proportions are independent of surface roughness and reflect their relative surface energies. Consequently, the external morphology of rutile nanometer- to micrometer-sized crystals imaged at the coarse scale of scanning electron microscope images is not an accurate indicator of the atomic smoothness or of the proportions of the steps present. Overall, our data strongly suggest that amino acids attach at these steps on the {110} surfaces of rutile.

Positive temperature coefficient of resistivity (PTCR) ceramics of 0.912(Ba1+xTiO3)–0.088(Bi0.5Na0.5TiO3) (BT–BNT) (x = −0.03 to 0.03) were prepared using the mixed oxide route and sintered at 1340°C for 4 h. Products were predominantly single phase with a tetragonal structure and grains in 2–6 μm size containing 90° ferroelectric domains. Samples with Ti/Ba > 1 contained second-phase Ba6Ti17O40. HRTEM and aberration-corrected Z-contrast high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) suggested that the dopants, Bi and Na, occupy the Ba site of the perovskite lattice, and revealed the presence of dissociated dislocations in x = −0.03 and x = 0.00 materials. The interval between two partial dislocations was 1.9–3.4 nm, yielding stacking fault energies of 363–649 mJ/m2. The PTCR behavior of the ceramics increased with Ti/Ba content, reaching a maximum of six decades change in resistivity for x = −0.03. The anomalous increase in resistivity depends critically on stoichiometry, increasing with the Ti/Ba ratio; this in turn is directly correlated with an increase in the amount of second-phase Ba6Ti17O40, an increase in the stacking fault energy, and an increase in the tilt angle of the grain boundaries.

The discovery of unusual nanorod precipitates in bismuth ferrite doped with Nd and Ti is reported. The atomic structure and chemistry of the nanorods are determined using a combination of high angle annular dark field imaging, electron energy loss spectroscopy, and density functional calculations. It is found that the structure of the BiFeO3 matrix is strongly modified adjacent to the precipitates; the readiness of BiFeO3 to adopt different structural allotropes in turn explains why such a large axial ratio, uncommon in precipitates, is stabilized. In addition, a correlation is found between the alignment of the rods and the orientation of ferroelastic domains in the matrix, which is consistent with the system's attempt to minimize its internal strain. Density functional calculations indicate a finite density of electronic states at the Fermi energy within the rods, suggesting enhanced electrical conductivity along the rod axes, and motivating future investigations of nanorod functionalities.

Grain boundaries (GBs) in polycrystalline Cu(In,Ga)Se 2 thin fi lms exhibit only slightly enhanced recombination, as compared with the grain interiors, allowing for very high power-conversion effi ciencies of more than 20% in the corresponding solar-cell devices. This work highlights the specifi c compositional and electrical properties of Cu(In,Ga)Se 2 GBs by application of appropriate subnanometer characterisation techniques: inline electron holography, electron energy-loss spectroscopy, and atom-probe tomography. It is found that changes of composition at the GBs are confi ned to regions of only about 1 nm in width. Therefore, these compositional changes are not due to secondary phases but atomic or ionic redistribution within the atomic planes close to the GBs. For different GBs in the Cu(In,Ga)Se 2 thin fi lm investigated, different atomic or ionic redistributions are also found. This chemical fl exibility makes polycrystalline Cu(In,Ga)Se 2 thin fi lms particularly suitable for photovoltaic applications.

Lanthanum doping of zirconium rich lead zirconate titanate gives rise to incommensurate, long-period antiferroelectric structures. The structure of two stacking sequences in this incommensurate phase is determined using quantitative analysis of high-resolution scanning transmission electron microscopy images, with the lead atom positions located with an exceptional precision of about 6 pm. This allows the estimation of local polarisation variations across the stacking units, and the polarisation varies in an approximately sinusoidal fashion along the stacking direction. The measured peak Pb atom displacements of about 28 pm and peak polarisation values of about 60 mu C cm-2 match extremely well to reported values for the commensurate antiferroelectric PbZrO3 phase.

We present and compare two different imaging techniques for plasmonic excitations in metallic nanoparticles based on high energy-resolution electron energy-loss spectroscopy in a monochromated transmission electron microscope. We demonstrate that a recently developed monochromated energy-filtering (EFTEM) approach can be used in addition to the well established scanning technique to directly obtain plasmon images in the energy range below 1 eV. The EFTEM technique is described in detail, and a double experiment performed on the same, triangular gold nanoparticle compares equivalent data acquired by both techniques, respectively.

Gold nanoparticles show optical properties different from bulk material due to resonance phenomena which depend on local structure and geometry. Electron energy-loss spectrometry (EELS) in scanning transmission electron microscopy (STEM) allows the spatially resolved measurement of these properties at a resolution of few nanometers. In this work, the first monochromated measurements of gold nanoparticles (spheres, rods and triangles) are presented. Due to the improved energy resolution of about 0.2 eV, surface plasmon excitations at energies below 1 eV could be accurately measured from raw experimental data.

The practical advantages of an electron monochromator for electron energy-loss spectroscopy (EELS) in transmission electron microscopy are described. Typical examples from materials and nanoparticle research demonstrate the use of EELS with high energy and spatial resolution. Recent instrumental developments are also reviewed with a discussion of how the technique could be used to study catalyst structures of the future.

The microstructure and phase composition of the protective Ti48Al2Ag coating produced on Timetal 834 by magnetron sputtering have been examined by scanning and analytical transmission electron microscopy (SEM, TEM). TEM investigations revealed that Ti48Al2Ag coating consists of two sublayers: outer columnar γ-TiAl and amorphous Ti5Al3O2. Energy-dispersive synchrotron radiation diffraction was applied for stress analysis. The results show that there are tensile residual stresses present within the Timetal 834 substrate and compressive residual stresses within the γ-TiAl sublayer.

Measuring low energy losses in semiconductors and insulators with high spatial resolution becomes attractive with the increasing availability of modern transmission electron microscopes (TEMs) equipped with monochromators, Cs correctors and energy filters. In this paper, we demonstrate that Cerenkov losses pose a limit for the interpretation of low energy loss spectra (EELS) in terms of interband transistions and bandgap determination for many materials. If the velocity of a charged particle in a medium exceeds the velocity of light, photons are emitted leading to a corresponding energy loss of a few electronvolt. Since these losses are strong for energies below the onset of interband transitions, they change the apparent loss function of semiconductors and insulators, with the risk of erroneous interpretation of spectra. We measured low energy losses of Si and GaAs with a monochromated TEM demonstrating the effect of sample thickness on Cerenkov losses. Angle resolved EELS and energy filtered diffraction patterns (taken without a monochromator) show the extremely narrow angular distribution of Cerenkov losses. The latter experiment provides a method that allows to decide whether Cerenkov radiation masks the very low loss signal in EELS.

Energy-filtering transmission electron microscopy (EFTEM), developed about ten years ago, is now a routine analysis tool in the characterization of materials. Based on the physical principles of electron energy-loss spectrometry (EELS), but with the addition of in-column or post-column energy-filters, it forms images of microstructures using a narrow energy band of inelastically scattered electrons. Post-column energy-filters, developed commercially by Gatan (Gatan Imaging Filter, GIF) in the early 1990s, could be attached to nearly any TEM. Almost at the same time, the introduction of the EM-912 microscope with an integrated � -filter by Zeiss, made it possible to use in-column filters as well. These two developments made EFTEM possible on an almost routine basis. The operation of these filters is rather straightforward and it is now possible to acquire element specific images within a few minutes. However, the optimal setup for data acquisition, the judicious choice of experimental parameters to solve specific materials science problems and the interpretation of the results can be rather difficult. For best results, a fundamental knowledge of the underlying physics of EELS and a systematic development of the technical details is necessary. In this work, we discuss the current status of EFTEM in terms of spatial resolution and illustrate it with a few technologically relevant applications at the nanometer length scale. © 2004 Elsevier B.V. All rights reserved.

Morphology and reflectance of carbonaceous material (CM) in Late Carboniferous metasediments of the eastern Greywacke Zone (Eastern Alps) indicate a mixture of vitrinite, grainy textured and lamellar shaped particles. As imaged by high-resolution atomic-force microscopy, vitrinite and the grainy textured particles show mesophase structures which can be described as facetted nanocrystals within the carbon matrix. High-resolution transmission electron microscopy has revealed two types of microtextures representing different degrees of graphitization. The first type is characterized by elongated ring-shaped microtextures, whereas the second type is characterized by graphite lamellae and polygonal flakes with long-range ordered aromatic layers. In spite of the heterogeneity of the CMs, the geographical distribution of quantitative metamorphic parameter (Raman spectra parameter, X-ray diffraction pattern, microscopic reflectance) suggests a graphitization process which is promoted by advective heat transport during post-collisional processes. In a tentative pressure-time path, Late Cretaceous thrusting results in a turbostratic ordering of the aromatic layer. Ordering to long-range ordered aromatic layers was achieved during the Late Cretaceous-Paleogene exhumation of mid-crustal rocks beneath the eastern Greywacke Zone.

Energy-filtering TEM (EFTEM) has turned out to be a very efficient and rapid tool for the chemical characterization of a specimen on a nanometer and even subnanometer length scale. Especially, the detection and measurement of very thin layers has become a great application of this technique in many materials science fields, e.g. semiconductors and hard disk technology. There, the reliability of compositional profiles is an important issue. However, the experimentally obtainable spatial resolution strongly influences the appearance of a thin layer in an EFTEM image, when dimensions reach subnanometer levels, which mainly leads to a broadening of the layer in the image. This fact has to be taken into account, when measuring the thickness of such a thin layer. Additionally, the convolution decreases contrast which makes the layer less visible in the image and finally determines the detection limit. In this work we present a systematic study on specifically designed Mn/PdMn multilayer test specimens to explore the practical aspects of spatial resolution and detection limits in EFTEM. Although specific to the ionization edges used, we will present general conclusions about the practical limitations in terms of EFTEM spatial resolution. Additionally, work will be shown about low energy-loss imaging of thin oxide layers, where delocalization is the main factor responsible for broadening.

A new cooperative transponder system for traffic safety applications is presented. The prototype system uses three different channels in a frequency range of 5.773 to 5.925 GHz to detect and localize vulnerable road users, infrastructure and other cars equipped with transponders in order to improve traffic safety, even under non-line of sight conditions. Two 10 MHz channels are used for ad-hoc network management, communication and angle of arrival estimation, while one 54 MHz channel is used for round-trip time of flight measurements, combining precise relative localization with data communication between equipped cars and multiple road users or infrastructure transponders. In the current implementation, data communication is carried out by an orthogonal frequency division multiplex link, while the distance measurement utilizes the idea of a secondary radar with pulse compression, using amplitude modulated pseudo noise codes and time division multiple access for multiuser support. This paper describes the system setup as well as an implementation of the prototype hardware and shows the current performance of the system in laboratory and real world measurements.

The basic foundation to enable safety-of-life applications in vehicular environments is the precise localization and path prediction of other road users in range. Currently available technologies like radar, camera or global positioning systems cannot meet most of the stringent requirements in terms of accuracy, reliability, update rate, and low outage probability imposed by this kind of applications. Radio based ranging methods using active transponders have already demonstrated their appealing capabilities like a low probability of outage and a very high range accuracy, even in multipath and non-line of sight conditions in urban areas. In order to allow full integration of such a system into IEEE 802.11p transceiver hardware and compatibility with existing Vehicle-to-Vehicle/Infrastructure applications, a method for range estimation based on orthogonal frequency modulated data symbols is described in this paper and a computationally simple implementation is presented.

Nanometric inclusions filled with nitrogen, located adjacent to FenN (n ¼ 3 or 4) nanocrystals within (Ga,Fe)N layers, are identified and characterized using scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS). High-resolution STEM images reveal a truncation of the Fe-N nanocrystals at their boundaries with the nitrogen-containing inclusions. A controlled electron beam hole drilling experiment is used to release nitrogen gas from an inclusion in situ in the electron microscope. The density of nitrogen in an individual inclusion is measured to be 1.4 6 0.3 g/cm3 . These observations provide an explanation for the location of surplus nitrogen in the (Ga,Fe)N layers, which is liberated by the nucleation of FenN (n > 1) nanocrystals during growth. Fil: Kovács, A.. Peter Grunberg Institute; Alemania Fil: Schaffer, B.. University of Glasgow; Reino Unido Fil: Moreno, Mario Sergio Jesus. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Jinschek, J. R.. FEI Company; Países Bajos Fil: Craven, A. J.. University of Glasgow; Reino Unido Fil: Dietl, T.. Polish Academy of Sciences; Argentina Fil: Bonanni, A.. Johannes Kepler University; Austria Fil: Dunin Borkowski, R. E.. Peter Grunberg Institute; Alemania

A 10kHz bandwidth 50Amax current sensor using a Hall effect gradiometer without magnetic core provides 80kHz update rate with a digital interface. Very low un-calibrated offset of 30mA (1σ) and after calibration typical 10mA over temperature is accomplished by a chopped multi-bit feedback continuous-time 3rd order ΔΣ-ADC. This also realizes low noise of 13mA rms in 1kHz signal bandwidth. The ADC uses enhanced chopping techniques and additional digital feedback loops to avoid chopper ripple. New analog and digital stress-compensation circuits with lateral and vertical n-doped resistors achieve lifetime gain drifts below 1% and temperature compensation. Auto-zeroing ping-pong comparators offer a fast over-current detection of 1…2μs on a dedicated output pin. The monolithic integrated sensor chip and the 4kV galvanic isolated current rail fit into a very small 7×7×1mm3 package.

This work presents results from high-resolution scanning transmission electron microscopy and electron energy-loss spectroscopy on twin boundaries (TBs) and nontwin grain boundaries (GBs) in CuðIn; GaÞSe2 thin films. It is shown that the atomic reconstruction is different for different symmetries of the grain boundaries. We are able to confirm the model proposed by Persson and Zunger [Phys. Rev. Lett. 91, 266401 (2003)] for Se-Se-terminated �3 f112g TBs, showing Cu depletion and In enrichment in the two atomic planes closest to the TB. On the contrary, Cu depletion without In enrichment is detected for a cation-Se-terminated TB. At nontwin GBs, always a strong anticorrelation of Cu and In signals is detected suggesting that the formation of InCu or CuIn antisites within a very confined region of smaller than 1 nm is an essential element in the reconstruction of these GBs.

The coupling of angstrom-sized electron probes with spin-polarized electronic transitions shows that the inelastically scattered probe electron is in a mixed state containing electron vortices with nonzero orbital angular momentum. These electrons create an asymmetric intensity distribution in energy filtered diffraction patterns, giving access to maps of the magnetic moments with atomic resolution. A feasibility experiment shows evidence of the predicted effect. Potential applications are column-by-column maps of magnetic ordering, and the creation of angstrom-sized free electrons with orbital angular momentum by inelastic scattering in a thin ferromagnetic foil.

This work presents results from high-resolution scanning transmission electron microscopy and electron energy-loss spectroscopy on twin boundaries (TBs) and nontwin grain boundaries (GBs) in Cu(In,Ga)Se(2) thin films. It is shown that the atomic reconstruction is different for different symmetries of the grain boundaries. We are able to confirm the model proposed by Persson and Zunger [Phys. Rev. Lett. 91, 266401 (2003)] for Se-Se-terminated Σ3 {112} TBs, showing Cu depletion and In enrichment in the two atomic planes closest to the TB. On the contrary, Cu depletion without In enrichment is detected for a cation-Se-terminated TB. At nontwin GBs, always a strong anticorrelation of Cu and In signals is detected suggesting that the formation of In(Cu) or Cu(In) antisites within a very confined region of smaller than 1 nm is an essential element in the reconstruction of these GBs.

Reactions at the interfaces can occur in metal inserted high-k gate stacks and are likely to evolve during device processing. Such reactions may affect the electrical properties of the stack and hence these could change during processing. The key interfaces are often not atomically flat and characterising the reaction layers on the near atomic scale required is a challenge. Aberration corrected scanning transmission electron microscopy (STEM) and spectrum imaging (SI) using electron energy loss spectroscopy (EELS) is used to characterise an HfN or Hf(O,N) reaction layer, ∼0.25 nm wide, between HfO2 and TiN. This demonstrates the very significant advances in high spatial resolution characterisation made in recent years.

While FIB sample preparation for transmission electron microscopy is a well established technique, few examples exist of samples of sufficient quality for atomic resolution imaging by aberration corrected (scanning) transmission electron microscopy (STEM). In this work we demonstrate the successful preparation of such samples from five different materials and present the refined lift-out preparation technique, which was applied here. Samples with parallel surfaces and a general thickness between 20 and 40 nm over a range of several μm were repeatedly prepared and analyzed by Cs-corrected STEM at 60 and 100 kV. Here, a novel ‘wedge pre-milling’ step helps to keep the protective surface layers intact during the whole milling process, allowing features close to or at the sample surface to be analyzed without preparation damage. Another example shows the cross-sectional preparation of a working thin film solar cell device to a final thickness of 10 to 20 nm over μm sized areas in the region of interest, enabling atomic resolution imaging and elemental mapping across general grain boundaries without projection artefacts. All sample preparation has been carried out in modern Dual-Beam FIB microscopes capable of low-kV Ga+ ion milling, but without additional preparation steps after the FIB lift-out procedure.

Electronic defects at interfaces between different materials or at extended structural defects such as grain boundaries (GB) or dislocations can deteriorate the performance of a semiconductor device considerably. Cu(In,Ga)Se2 (CIGS) thin-film solar cells consist of several interfaces between individual layers of different materials. In addition, the main light-absorbing layer, the CIGS absorber, exhibits a high density of GBs (i.e., the average grain size is typically smaller than the layer thickness) as well as of dislocations (up to 10 10 cm -2 in high-efficiency solar cells [1]). Still, CIGS solar cells exhibit highest power-conversion efficiencies of up to 20.8 % [2]. Today, the roles of interfaces and extended structural defects in the solar-cell device are not yet fully understood, although extensive research efforts have been made. We applied various methods in transmission electron microscopy (TEM), such as inline electron holography, electron energy-loss spectroscopy (EELS), as well as energy-dispersive X-ray spectroscopy (EDS) in order to obtain more information about these features.

Ceramics of 0.9La2/3TiO3–0.1LaAlO3 prepared by the mixed oxide route were sintered at 1400°C in air for 4 h and cooled at rates 180°–1°C/h. The products were at least 97% dense with grain sizes of 7–10 μm and relative permittivities 66.9±0.7 at 4 GHz. Rapidly cooled samples (180°C/h) were single phase and exhibited the highest dielectric Q×f values of 16 300±900 GHz. High-resolution transmission electron microscopy revealed microtwins and domains in all the ceramics, with the highest density of both features in the rapidly cooled samples. A-site vacancies in rapidly cooled 0.9La2/3TiO3–0.1LaAlO3 ceramics were imaged by aberration-corrected scanning transmission electron microscopy. It is shown that vacancies and La1 atoms occupy the 4(h) sites and the 4(g) site is fully occupied by La2 atoms in the orthorhombic Cmmm structure of lanthum titanate. The microtwin boundaries in the microstructure of La2/3TiO3 stabilized by LaAlO3 lie on the La2 atomic planes. On twinning, La2 and La1 atoms share the same site. The sharing of the 4(h) and 4(g) atomic sites at the twin boundaries is a mechanism to reduce lattice strain upon the continuous transformation from a high-temperature simple cubic Fm3m form to a low-temperature orthorhombic Cmmm form, which involves vacancy/cation ordering and anti-phase tilting of the oxygen octahedra.

The analysis of TEM low-loss electron energy-loss spectra i.e. the range up to 50 eV, has recently become attractive and feasible with the advent of advanced TEM equipment and analysis instrumentation, such as monochromators and improved energy-filters / spectrometers [1,2]. The better energy resolution opens up new possibilities for a more accurate measurement of bandgaps and optical properties via the dielectric function. However, a crucial step in the analysis of valence EELS data is the separation of the zero-loss peak [3], ranging into the spectral regime between 0–5 eV. A monochromator can help shortening the tail by narrowing the peak itself, and secondly it makes the shape symmetric, facilitating the study of the band-gap region considerably, even with narrow band-gap semiconductors. On the other hand, physical effects like Cerenkov excitation may pose a limit to the accuracy of band structure investigations, which are further influenced by experimental parameters, bandgap character and / or specimen thickness. Despite the instrumental improvements, the handling of dynamically changing intensities in the low-loss area and the correction of artifacts caused by energy- and spatial drift as well as residual aberrations require an elaborated data acquisition and post-processing scheme, including extra interactivity, robustness and flexibility [4].

We demonstrate the imaging capabilities of energy-filtered transmission electron microscopy at high-energy resolution in the low-energy-loss region, reporting the direct image of a surface plasmon of an elongated gold nanoparticle at energies around 1 eV. Using complimentary model calculations performed within the boundary element method approach we can assign the observed results to the plasmon eigenmodes of the metallic nanoparticle.

In this work we show how energy-filtered imaging can be used to obtain spectrum images of electron energy-loss spectrometric data. Focus is placed on improved energy resolution within these data sets. Using two multilayer samples (GaN/AlN and InP/InAs), we demonstrate the advantages of spectrum-imaging and its extended mapping capabilities. Plasmon-ratio maps are used to quickly create high-contrast material maps with high signal-to-noise ratio, ratio-contrast plots are used to gain optimum settings for the ratio maps, and plasmon-position maps are used to map small shifts of the energy position of bulk plasmon peaks.

Tire pressure monitoring systems (TPMS) are gaining importance due to improved security standards in the automotive industry. In active systems, the power consumption of the system is of utmost importance for a required lifetime of more than 10 years. The presented integrated circuit comprises high resolution pressure, temperature and voltage monitoring, low-power oscillators, a specialized DSP with RAM/ROM and an EEPROM to store calibration data. The continuously running low-power oscillator for internal wake-up timing is operated with 30 nA. Due to the extremely low-power consumption of all circuit blocks, pressure measurements can be carried out in short intervals (0.5 s). This enables the implementation of a new intelligent dynamic wake-up algorithm to optimize the power-intensive HF-transmission intervals under different driving situations. Thus additional rotation detectors are not needed any more. The charge consumption without HF-transmission results in 48 mAh in 10 years.

An integrated GMR (giant-magnetic-resistance) sensor is presented for 360deg angular measurements of rotating magnetic fields in automotive applications. The spin-valve GMR-layers are directly applied to a standard semiconductor 0.22 mum CMOS process by vertical integration of the sensor-bridges atop of active circuitry. The entire integrated angle-sensor comprises 2 orthogonal magnetized GMR-bridges for sine and cosine signal measurements, and the subsequent signal conditioning circuitry. The entire angular sensor is designed to work in harsh automotive environment in a temperature range of -40degC to 150degC. The strength for best precision covers a wide range from 20 to 50 mT. The resulting angular information itself can be obtained by SPI-readout and calculating the arc-trigonometric function of the bridge signals with a resolution of >13 bit in an auxiliary microcontroller. After individual calibration to compensate for production spread an accuracy of typical 0.5deg is achieved.

We present a fully automated method for three-dimensional (3D) elemental analysis demonstrated using a ceramic sample of chemistry (Ca)MgTiO(x). The specimen is serially sectioned by a focused ion beam (FIB) microscope, and energy-dispersive X-ray spectrometry (EDXS) is used for elemental analysis of each cross-section created. A 3D elemental model is reconstructed from the stack of two-dimensional (2D) data. This work concentrates on issues arising from process automation, the large sample volume of approximately 17 x 17 x 10 microm(3), and the insulating nature of the specimen. A new routine for post-acquisition data correction of different drift effects is demonstrated. Furthermore, it is shown that EDXS data may be erroneous for specimens containing voids, and that back-scattered electron images have to be used to correct for these errors.

A linear 4kHz Hall sensor in 0.6mum BiCMOS has digital 3rd-order temperature compensation, a DR of 90dB and an offset of 50muT. It uses a chopped 3rd-order multibit CT-DeltaSigma ADC including an up/down counter loop and bandgap-based compensation for stability and accuracy. Digital compensation of sensitivity drift caused by package-induced stress is provided