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Energy-dispersive X-ray spectroscopy (EDXS) in a transmission electron microscope is frequently used for the chemical analysis of Cu(In,Ga)Se2 (CIGS) solar cells with high spatial resolution. However, the quantification of EDXS data is complicated due to quantification errors and artifacts. This work shows how quantitative EDXS analyses of CIGS-based solar cells with Zn(O,S) buffer and ZnO-based window layers can be significantly improved. For this purpose, CIGS-based solar cells and a reference sample with a stack of Zn(O,S) layers with different [O]/[S] ratios were analyzed. For Zn(O,S), the correction of sample-thickness-dependent absorption of low-energy O–Kα X-rays significantly improves the results of quantitative EDXS. Absorption of characteristic X-rays in CIGS is less relevant. However, for small transmission electron microscopy (TEM) sample thicknesses, artifacts can occur due to material changes by focused-ion-beam (FIB)-based preparation of TEM samples, electron-beam-induced damage, and oxidation of the sample surface. We also show that a Pt-protection layer, deposited on the sample surface before FIB preparation of TEM lamellae, can induce artifacts that can be avoided by first depositing a carbon layer.

The synthesis of semiconductor nanowires is more and more interested to the applications for building blocks of the innovative nano-sized devices and circuits, but the research and fabrication of these nanowires are also holding a number of difficulties and challenges. Among many different kinds of semiconductor nanowires, Ga2O3 is increasingly grown for many promising applications in nano-device production, namely nanowire LED and Laser. So far there are many synthesizing methods of semiconductor nanowires, among them the vapor–liquid–solid (VLS) method is simple, cheap and popular. However, when we use the VLS method for nanowire growth, various technological problems exist. This paper aims at investigating some influences of the growth technological conditions and Au metal catalyst on the morphology of Ga2O3 nanowire grown by VLS on GaAs substrate. The main considering factors include the different growing temperatures and times, the effects of Au diffusion, Au droplets formation, Au cluster islands formation, and gas volume of the growing tube/ampoule at the 10−1 torr low air pressure. The obtained experimental results regarding the structural properties of nanowires under these effects investigated by scanning electron microscopy, field emission scanning electron microscopy, high angle annular dark field and bright field, scanning transmission electron microscopy, energy-dispersive X-ray techniques, and focus ion beam are presented and discussed.

Thin Ni/Al and Ni/Ga layers of different atomic ratios were codeposited onto Si(001) at room temperature followed by subsequent annealing. Influence of annealing temperature on morphology and composition of ternary disilicide NiSi2-xAlx and NiSi2-xGax layers was investigated by transmission electron microscopy. Addition of Al or Ga leads to a decrease of the disilicide formation temperature from 700°C down to at least 500°C. Depending on the composition closed, uniformly oriented NiSi2-xAlx and NiSi2-xGax layers were observed after annealing at 900°C, whereas reaction of a pure Ni film with Si leads to the island formation with a mixture of A- and B-type orientations.

The development of modern technology affects the science of small objects in two ways. On one hand better means for handling, imaging and analysis of miniature objects are provided, which means we can try and understand our world on a much smaller scale. On the other hand further miniaturization in manufacturing necessitates the control of technological processes at a minimum of one order of magnitude below the aspired device size. The need for rapid and efficient nanoanalysis is growing very quickly. The next generation 22 nm node in microelectronics architecture is approaching. New solutions for electronic interconnects, capacitors, denser data storage and solar cells are currently under development. This requires atomic scale analysis of a wide range of materials such as functionalized carbon nanotubes (CNTs), various perovskites and three-dimensional nanostructures. Another important field of miniaturization is modern medicine. It strives to identify toxic nanoparticles and transfer medication and operation tools precisely to the place where they are needed in the body. For all of this nanoanalysis is irreplaceable. To understand and control the function of miniature sized natural and artificial objects we need to know their element distribution.

The study reports on the structure of thin ternary NiGaxSi2–x silicide layers grown on Si(001) by Ni/Ga codeposition at room temperature followed by subsequent annealing. The influence of both the Ga content and the annealing temperature on the phase formation and orientation of the layers was investigated for the first time. Addition of Ga leads to a decrease of the disilicide formation temperature down to less than 500 °C. Island formation is observed for the Ga content of 0.17 after annealing above 900 °C. The NiSi2-xGax islands grow with a NiSi2–xGax(110) ‖ Si(001) texture. In contrast, closed epitaxial NiSi2–xGax layers of A-type are obtained for the Ga content of 0.28 after annealing at 900 °C. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Deposition of one monolayer of Sb prior to the deposition of Mn at 600 °C is observed to increase the MnSi 1.7 island density by about two orders of magnitude as well as to change the crystalline orientation of the silicide grains. The preferential epitaxial orientation of MnSi 1.7 grains grown by this process is determined to be MnSi 1.7 (1 0 0)[0 1 0]||Si(0 0 1)[1 0 0]. This growth procedure results in the silicide growth into the Si matrix. For comparison, the same deposition process carried out without Sb leads to silicide formation on top of the substrate surface. The observed morphological changes of the MnSi 1.7 layers can be explained by a reduced surface diffusion of the Mn atoms on Si(0 0 1) in presence of the Sb monolayer. Additionally, lateral Si diffusion is considered to be nearly suppressed, which is responsible for the observed silicide growth into the substrate.

A systematic distortion in high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM) images, which may be caused by residual electrical interference, has been evaluated. Strain mapping, using the geometric phase methodology, has been applied to images acquired in an aberration-corrected STEM. This allows this distortion to be removed and so quantitative analysis of HAADF-STEM images was enabled. The distortion is quantified by applying this technique to structurally perfect and strain-free material. As an example, the correction is used to analyse an InAs/GaAs dot-in-quantum well heterostructure grown by molecular beam epitaxy. The result is a quantitative measure of internal strain on an atomic scale. The measured internal strain field of the heterostructure can be interpreted as being due to variations of indium concentration in the quantum dot.

Epitaxial cobalt disilicide thin films buried in (001) silicon were grown by annealing a precipitate distribution in a nearly undisturbed Si matrix. The CoSi2/Si junction was studied by dedicated aberration-corrected scanning transmission electron microscopy. Earlier, we unequivocally identified two different interface structures, the atomic arrangement and frequency of appearance of which are consistent with predictions from total energy calculations. This paper is dealing with the interface dislocations in more detail. Due to the cubic crystal symmetry of both, the silicide and the Si substrate, the interface consists of a patchwork of different domains, which are rotated to each other by 90°. Dislocations are required at the boundaries of those domains. Additionally, Misfit dislocations are expected, since under the applied conditions for non-pseudomorphic growth a relaxed interface is formed. A complex defect structure at the interface domain boundaries, always associated with {111}-facets was found to solve both constraints, thereby minimising the interface energy of the system efficiently.

Systematic distortion has been analysed in high-angle annular dark-field (HAADF) images which may be caused by electrical interference. Strain mapping techniques have been applied to a strain-free GaAs substrate in order to provide a broad analysis of the influence of this distortion on the determination of local strain in the heterostructure. We have developed a methodology for estimating the systematic distortion, and we correct the original images by using an algorithm that removes this systematic distortion.

The study reports on the Sb mediated growth of NiSi2 on Si(0 0 1) in the temperature range from 350 to 600 °C. Reactive deposition of Ni onto Si(0 0 1) in this temperature interval without the surfactant Sb leads to the formation of NiSi2 islands. The NiSi2 grains have pyramidal shape and grow from the Si surface into the substrate. They have the so-called A-type orientation. Deposition of about one monolayer of Sb onto Si(0 0 1) prior to reactive deposition of Ni leads to a relocation of the NiSi2 nucleation from the Si(0 0 1) surface to the artificially created Si buffer interface. In this case three types of NiSi2 crystallites, which differ in their shape and orientation, grow embedded into the Si matrix.

The morphology and texture of CrSi2 films grown on Si(0 0 1) is reported. The films have been prepared under ultra high vacuum conditions by reactive codeposition and by the template method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses have been performed to investigate the influence of the substrate temperature and the template thickness on the silicide texture and morphology. XRD evidences that the major part of CrSi2 crystallites grows with an orientation of CrSi 2 (0 0 1)[1 0 0]∥ Si (0 0 1)[1 1 0] within all present experiments. Considering the morphology and preferred orientation of the crystallites the substrate temperature of 700 °C is determined to be optimal for the codeposition growth method. A further improvement of the CrSi2(0 0 1) texture and an increase of the grain size by an order of magnitude is observed after deposition of 0.5 nm Cr onto the Si(0 0 1) substrate at room temperature prior to the codeposition of Cr and Si at 700 °C.

We report on the growth of thin titanium silicide layers on Si(001) by surfactant-mediated reactive deposition (SMRD) at temperatures in the range of 300-800 °C. The surface diffusion of Ti and Si is crucial for the morphology of the growing silicide layer and can be altered by the presence of a surfactant (here Sb). Samples prepared with and without Sb were analysed by SEM, RBS, TEM and XRD. The results show that the phase of the growing silicide is not influenced by the surfactant. For temperatures higher than 400 °C, the C49-disilicide phase was found. The SEM investigations show that the pinhole density in the TiSi2 layer is significantly reduced by the surfactant.

This study reports on transmission electron microscopy investigations of higher manganese silicide (HMS) layers grown by molecular beam epitaxy (MBE) on (001)Si using the surfactant mediated reactive deposition technique. Applying Sb as a surfactant (surface active substances) results in an increased silicide island density as well as in a change in the crystalline orientation of the silicide islands. The silicide islands were found to grow into the Si matrix. The preferential epitaxial relationship was determined to be (100)[010]Mn4Si7 || (001)[100]Si or (010)[??00]Mn4Si7 || (001)[100]Si. In [100]Si cross-sectional view the silicide crystallites of this orientation appear with a smooth Mn4Si7/(010)Si interface and a slightly inclined to (001)Si Mn4Si7/Si interface, which is suggested to split up into two local sections: Mn4Si7/(001)Si and Mn4Si7/(011)Si.

Semiconducting higher manganese silicides (HMS) with a composition near that of MnSi1.7 are of special interest due to their thermoelectric properties. We report on the growth of HMS layers deposited by MBE using the template technique. In particular the influence of the template thickness on the structure and morphology of MnSi1.7 films on (001)Si substrates was investigated. It was found that there is an optimal template thickness that causes preferred epitaxial growth of the major amount of the silicide. Three different epitaxial orientation relations of the silicide crystals to the substrate were observed. Considering the specific features of the electron diffraction patterns of MnSi1.7 the HMS phase was identified as Mn4Si7.

The silicides of manganese most rich in silicon, the so-called higher manganese silicides (HMS) have a composition MnSix with x in the range from 1.67 to 1.75. This material group with a tetragonal crystal structure shows semiconducting electronic properties promising the application in thermoelectric devices (C.B. Viniing, Proceedings of the IX International Conference on Thermoelectrics, California Institute of Technology, Pasadena, 1991 249). This paper reports on structural and morphological properties of the HMS prepared on Si(0 0 1) by various MBE processes under UHV conditions. The deposition of Mn only as well as the codeposition of Mn and Si do not allow epitaxial growth of the HMS. But, after the preparation of a thin Mn template at room temperature, the codeposition of Mn and Si at high substrate temperatures results in the growth of epitaxial HMS. The fraction of epitaxially grown HMS strongly depends on the thickness of the template layer. The epitaxial relationship between the silicide and the Si has been determined by X-ray diffraction.

Thin films of different metals M (M=Ti, Zr, Hf, Nb, Fe, and Ni) of thickness around 10 nm are deposited on Si(100) substrates and a ∼30 nm Co film is deposited on these metal films using the magnetron sputtering method. Cross-sectional transmission electron microscopy (XTEM) shows the presence of a ∼2 nm buried ultrathin amorphous interlayer at the interface between the Co layer and the M layers (M=Ti, Zr, Hf, and Nb). X-ray reflectivity is used to determine the electron density of this buried ultrathin amorphous interlayer. X-ray diffraction (XRD) is used to determine the crystalline quality of the deposited Co film on these various metal film substrates. The XRD peaks of Co(111) and Co(222) are observed when Ti, Zr, Hf, and Nb are used as substrates. Pole figure measurements confirm that the Co film is highly textured on such metallic substrates. On the other hand no characteristic XRD peaks of cobalt are observed when Ni and Fe are used as the substrate, however, XTEM shows the presence of the Co film ...

TEM and RBS studies of the solid phase reaction of Co/Ti- and Co/Hf/Si(001) layer systems are reported. In addition to conventional annealing procedures a special thermal treatment was applied to investigate the intermediate stages of the reaction during heating up. With rising temperature a complex Co–Si-phase sequence was observed which finally results in the growth of epitaxial CoSi 2 . The emerging silicide phases were proved to grow with preferred orientation relations to the substrate. The observed growth behaviour is compared for both the systems and discussed considering aspects of energy minimization and material supply under the conditions of a thin film reaction.

The most rich silicon silicides of manganese, the group of higher manganese silicides (HMS), have the composition MnSix with x in the range from 1.67 to 1.75. This material group with a tetragonal crystal structure shows semiconducting electronic properties, with promising application in thermoelectric devices. This paper reports the structural and morphological properties of HMS prepared by a reactive deposition process on Si(001) under UHV conditions. X-ray diffraction shows, for all samples grown at substrate temperatures ranging from 400 to 750°C, the growth of HMS only. Scanning electron microscopy and Rutherford backscattering spectrometry show a transition from film growth to island growth with increasing substrate temperature. A detailed analysis of the XRD spectra shows a change of the texture of HMS at the transition of the sample morphology. The results are discussed on the basis of anisotropic growth rates for differently oriented grains of HMS.

The presence of a buried, ultra-thin amorphous interlayer in the interface of room temperature deposited Ni film with a crystalline Si(100) substrate has been observed using cross sectional transmission electron microscopy (XTEM). The electron density of the interlayer silicide is found to be 2.02 e/A3 by specular X-ray reflectivity (XRR) measurements. X-ray diffraction (XRD) is used to investigate the growth of deposited Ni film on the buried ultra-thin silicide layer. The Ni film is found to be highly textured in an Ni(111) plane. The enthalpy of formation of the Ni/Si system is calculated using Miedema’s model to explain the role of amorphous interlayer silicide on the growth of textured Ni film. The local temperature of the interlayer silicide is calculated using enthalpy of formation and the average heat capacity of Ni and Si. The local temperature is around 1042 K if the interlayer compound is Ni3Si and the local temperature is 1389 K if the interlayer compound is Ni2Si. The surface mobility of the further deposited Ni atoms is enhanced due to the local temperature rise of the amorphous interlayer and produced highly textured Ni film.

The reaction of Co with epitaxial Si 1− y C y (001) films is investigated with regard to dependence on annealing temperature and C concentration y . Resistance measurements and RBS analysis reveal a small increase in the disilicide formation temperature. The electrical properties are very similar for thin CoSi 2 films grown at 650°C on Si 0.999 C 0.001 and on Si. Whereas the CoSi 2 is fully polycrystalline on Si(001), partially oriented CoSi 2 has been observed on C-containing substrate layers. An increase of the number of epitaxially grown CoSi 2 crystallites has been observed with increasing C concentration.

Plasma etching of epitaxial CoSi 2 films with a ternary Co–Ti–Si top layer formed during solid phase reaction of Co/Ti bilayers on Si(100) was investigated. By using a pure argon-RF-plasma the ternary top layer was sputtered without formation of a disturbing overlayer. The main disadvantage of this process is the formation of a crater-like surface morphology connected with a strong increase of the surface roughness. Etching the ternary top layer by a reactive process (CF 4 /Ar) leads to a smoother surface, but a Co–fluoride film was grown on top of the silicide surface. In a following argon etch process this disturbing overlayer can be removed completely, simultaneously the roughness of the etched silicide surface is reduced considerably.

The disilicide of Co is a promising metallic material for the submicron technology with the advantage of a low specific resistivity as well as of a low preparation temperature. A further downscaling in the Si technology requires in addition to lower process temperatures an effective conservation of dopant distributions. One method for trapping doping profiles is the admixture of a small concentration of carbon to the Si. This paper reports on the Co silicide formation on Si 0.999 C 0.001 (001) substrate layers. The Co films were deposited by e-beam evaporation under UHV conditions. To investigate the reaction of the Co films with the substrate layers performed by rapid thermal annealing the samples were characterized by Rutherford backscattering and measuring the electrical resistance at room temperature. Compared with Si(001) a small increase of the thermal budget for the CoSi 2 formation on Si 0.999 C 0.001 (001) has been found. For samples annealed at 650°C for 30 s the resistivity in dependence on temperature was determined. The analysis of this data using the Bloch–Gruneisen equation reveals a good electrical quality of the prepared CoSi 2 films.

A CF 4 /Ar RF plasma has been applied to etch epitaxial CoSi 2 films as well as compound layers containing mainly Co, Ti and Si. This additional layer is formed on top of the CoSi 2 during the solid phase reaction of a Co/Ti bilayer with Si(100). The etch rate for CoSi 2 depends strongly on the RF power. Below 18 W the etch rate is negligibly small. By increasing the power up to 90 W the etch rate increases linearly up to 20 nm/min. The disturbing top layer could be removed easily at 60 W with an estimated etch rate of 15 nm/min. But, at the beginning of the etching process there is formed a new fluorine containing uniform overlayer on top of the CoSi 2 film. This nonvolatile overlayer is partially removed at its surface by sputtering. But, it grows simultaneously at the interface to CoSi 2 by the reaction of CoSi 2 with F diffused through the overlayer. Consequently the thickness of the overlayer remains constant and the sputtering process determines the etch rate of the underlying CoSi 2 film. It was demonstrated, that an in situ control of the etching process is possible using laser interferometry.

Allotaxy is a special method to grow epitaxial heterostructures. An important role in this process is the distribution of the crystallites of the compound AB X in the matrix A. This study concerns the first step of allotaxy in the Ni–Si system, that is, the preparation of the precipitate distribution. To investigate the influence of the deposition conditions on the growth and arrangement of the precipitates the substrate temperature as well as the deposition rate have been varied. RBS measurements revealed the redistribution of the deposited Ni already during the deposition process resulting in precipitate coarsening. This effect increases with increasing substrate temperature and decreasing deposition rate. A strong diffusion of Ni atoms towards the sample surface has been observed. The TEM analysis shows that oriented cubic NiSi 2 is grown. Under appropriate deposition conditions self-assembling of the NiSi 2 precipitates has been observed.

Among the epitaxial transition metal silicides CoSi 2 is of special interest for applications in ULSI technology due to its high thermal stability and low electrical resistivity. The solid phase reaction of metallic bilayers with Si in an N 2 ambient is a well-known process for growing epitaxial CoSi 2 . However, the real function of the so-called diffusion barrier, which is arising during the annealing process, remains unclear. TEM studies revealed the intermediate growth of a CoSi phase with grains of preferred orientation to Si. The growth of this phase raises the temperature of CoSi 2 nucleation, which starts at the CoSi/Si interface. The nucleation temperature determines the quality of the growing epitaxial CoSi 2 , which is better for Ti as a barrier forming material than for Hf, also used successfully. Whether an intermediate oriented growth of CoSi is promoting the epitaxial quality of CoSi 2 otherwise than by shifting the nucleation temperature, remains an open question.

The epitaxial CoSi/sub 2/ formation on Si(100) by Co/Ti bilayers through solid phase epitaxy is well known. The surface layer consists of TiN or CoTi/sub x/Si/sub y/, depending on the experimental conditions. The role of the barrier layer is to reduce the natural oxide and to limit the flux of the Co atoms into the Si substrate. Several other metals, as Cr, V, Ta and Zr have been used as a barrier layer. We investigated Hf as barrier material in comparison with Ti and Zr barriers. All these materials are able to reduce the natural oxide on silicon.

Thin films of the lanthanoide diphthalocyanines LnPc2 (Ln: Ho, Er) are deposited onto NaCl (001) surfaces by thermal evaporation under high vacuum conditions and analysed by HRTEM. Based on the obtained images a model is describing growth and structure of these films. The thin films consist of columnar crystallites with lateral dimensions of 10 to 100 nm mainly of the tetragonal phase with a two-molecular base made of the two isomeric forms of the LnPc2 molecule. According to this model each (001) plane of the crystallites is made of exclusively one of the two mirror-symmetric LnPc2 isomers. The type of isomer is alternating from plane to plane. Depending on the lowest plane the growth of the crystallites is preferably continued laterally in two mirror-symmetric direction sets, because of the interactions with the substrate. Staggering angles of 36.9° and 53.1°, respectively, between the crystallites occur, as is well known from literature. Small pieces of orthorhombic structure and increased concentrations of lattice defects arise in the regions between the tetragonal crystallites and at the grain boundaries. Dunne Schichten der Lanthanoiddiphthalocyanine LnPc2 (Ln: Ho, Er) werden auf NaCl (001) Oberflachen durch thermische Verdampfung im Hochvakuum abgeschieden und mittels HRTEM untersucht. In Auswertung der erhaltenen Bilder wird ein Modell entwickelt, das das Wachstum und die Struktur dieser Schichten beschreibt. Die dunnen Schichten bestehen aus saulenformigen Kristalliten mit einer lateralen Ausdehnung von 10 bis 100 nm in hauptsachlich tetragonaler Phase mit einer zweimolekularen Basis aus den beiden isomeren Formen des LnPc2-Molekuls. Nach diesem Modell besteht jede (001) Ebene der Kristallite aus ausschlieslich einem der beiden spiegelsymmetrischen LnPc2-Isomere. Der Isomertyp wechselt von Ebene zu Ebene. Abhangig von der untersten Ebene erfolgt das Kristallitwachstum aufgrund von Wechselwirkungen mit dem Substrat lateral bevorzugt in zwei spiegelsymmetrischen Orientierungen. Zwischen den Kristalliten treten die aus der Literatur bekannten Winkel von 36,9° und 53,1° auf. In den Bereichen zwischen den tetragonalen Kristalliten und an den Korngrenzen entstehen kleine Gebiete orthorhombischer Struktur und hohere Konzentrationen von Gitterdefekten.

Individual heteroatoms in nanoscale materials often play a pivotal role in materials properties. To obtain maximum control over materials properties, researchers must be able to detect and identify diverse heteroatoms in samples with varying thickness and composition. Here, we demonstrate the identification of individual Si, S, P, and Ca heteroatoms in two-phase carbonaceous nanoscale mixtures with energy dispersive X-ray spectroscopy in a scanning transmission electron microscope. In order to fully demonstrate the robustness of the technique and the potential advantages over electron energy loss spectroscopy for single-atom speciation, no a priori constraint was placed on the sample thickness or types of heteroatom species. The various heteroatoms were identified with X-ray spectrum collection times ranging from 8 to 57 s, and normalized count rates of 0.096–0.007 counts s−1 pA−1. The lowest times/highest effective count rates were achieved by maximizing the effective dwell time on the atom, through mini...

We have presented systematic cross-plane thermal conductivity (λ) data for the undoped strain-symmetrized Si/Ge superlattices grown on Si(111) with superlattice (SL) period thickness varying from 3.6 to 16 nm. In thin SL period (L⩽7 nm) samples, the data have shown considerable reductions of λ, by more than 50% and 30% compared to the SiGe alloy and to the earlier reported values in (100)-oriented Si/Ge superlattice structures (SLS), respectively. For the thick SL period samples (L>10 nm), λ has shown a tendency to saturate at the SiGe alloy value. This is understood as, with increasing L, the SLS breaks and the SiGe alloying starts to grow. This structural behavior is clearly observed in the cross-plane transmission electron microscope images as well. In addition to these, for the thin SL period (L⩽7 nm) samples, the data have shown a shallow minimum which is attributed to the competing behavior of the wave nature and the classical particle nature of the localized phonons. Nevertheless, the present study...

Thin CoSi2 films have been grown on Si(100) substrates using the relative deposition epitaxy method. The structure of the silicide films have been analyzed using x-ray diffraction, transmission electron microscopy (TEM), and Rutherford backscattering spectrometry and channeling, and the interface roughness of the CoSi2/Si(100) is analyzed using specular x-ray reflectivity and cross-sectional TEM. The structure and interface roughness of CoSi2/Si(100) is found to be dependent on the substrate temperature. Highly epitaxial CoSi2 with minimum interface roughness is obtained when the film is grown at substrate temperatures around 900 K. The observed interface roughness is a parabolic function of temperature. The achievement of the best silicide at a substrate temperature around 900 K is explained on the basis of the instantaneous diffusion of Co through growing CoSi2.

Nickel monosilicide (NiSi) is a promising material for electrical contacts and interconnects in the latest generation of CMOS devices [1]. Despite already being used in certain industrial applications, there is a lack of information, especially about chemical or structural variations in nanometer scale compounds. With continuing miniaturisation, knowledge of such variations is crucial for successful application. Another important aspect is the thermal stability of the low-resistivity NiSi phase which generally changes into the disilicide (NiSi2) at a temperature of 700°C. This phase transformation can be shifted towards higher temperatures by alloying with Pt [2].

Silicide-silicon interfaces were studied at the superSTEM Laboratory using aberration corrected dedicated STEM at 100kV. With suitable samples the resolution of about 0.1 nm allows compositional defects of atomic dimension to be visualised in high angle annular dark field (HAADF) images. Cubic metal silicides grown epitaxially on cubic (001) Si were chosen for these investigations, since, in case of bulk crystals on a [110] zone axis, only pure metal and pure silicon columns face the electron beam. At the interface however, strain and differences in chemical solubility can produce various, mostly periodically appearing one-dimensional defects.

The statistical distribution of grain orientations in a poly-crystalline thin film, called texture, is an important characteristic. The presence of preferred orientations is important for the macroscopical behaviour of the film due to an anisotropy of certain properties, like resistivity, carrier mobility, etc. Therefore it is important to know, which types of texture evolve for a certain combination of substrate and film material and in which way they depend on the sample preparation.