The molecular dynamics of poly(2-vinyl-pyridine) (P2VP) brushes is measured by Broadband Dielectric Spectroscopy (BDS) in a wide temperature (250 K to 440 K) and broad spectral (0.1 Hz to 1 MHz) range. This is realized using nanostructured, highly conductive silicon electrodes being separated by silica spacers as small as 35 nm. A "grafting-to"-method is applied to prepare the P2VP-brushes with five different grafting densities (0.030 nm(-2) to 0.117 nm(-2)), covering the "true-brush" regime with highly stretched coils and the "mushroom-to-brush" transition regime. The film thickness ranges between 1.8 to 7.1 (±0.2) nm. Two relaxations are observed, an Arrhenius-like process being attributed to fluctuations in the poly(glycidyl-methacrylate) (PGMA) linker used for the grafting reaction and the segmental dynamics (dynamic glass transition) of the P2VP brushes. The latter is characterized by a Vogel-Fulcher-Tammann dependence similar to bulk P2VP. The results can be comprehended considering the length scale on which the dynamic glass transition (≤1 nm) takes place.

The incubation time t0 of the crystallization of intrinsic and P, B‐doped amorphous silicon‐germanium (a‐Si1–xGex: H) layers deposited on SiO2/Si(100) substrates is studied as a function of temperature and composition using in situ transmission electron microscopy (TEM). The temperature dependence of t0 follows an Arrhenius behavior t0 = t0* exp (W/kT) with activation energy W and prefactor t0* depending on x. The dependences of grain growth, nucleation rate as well as of the morphology of the polycrystalline films on temperature, doping, and composition are estimated. Doping SiGe films with B decreases grain growth rate during crystallization. Independent of the Ge content, such films stay nanocrystalline (grain size ≪10 nm) up to an annealing temperature of 800°C. During crystallization decomposition within SiGe films is observed. Furthermore, metal‐induced crystallization in the Al/a‐Si1–xGex:H structures is demonstrated.

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Spatial distribution and properties of oxide were examined in 300 mm nitrogen (N) doped CZ-Si. Experimentally grown materials with N ranging from ∼ 10 13 cm −3 to 10 15 cm −3 were studied by infrared light scattering tomography, scanning infrared microscopy, transmission electron microscopy and electron beam induced current. It was established that an increasing N content improves the uniformity of the radial distribution of precipitates in the bulk of the wafer, the density of precipitates reaching a level of ∼ 10 9 cm −3. The width of the denuded zone varies in the range from 15 µm to 70 µm depending on radial position and N doping level. Electron microscopy revealed lower oxide precipitate densities of about 10 5 to 10 8 cm −3. The results are interpreted in terms of existence of agglomerates of nanometer size precipitate nuclei and/or by the defect-induced strain relaxation around the precipitates.

The submicroscopic structure of synthetic Hg,Cl, monocrystals was investigated by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM), indirect imaging of surfaces (Pt/C replica technique) as well as by application of supplementary methods. As already reported by NEUMANN et al., TEM-images show a periodic stripelike contrast whose period varies from 0.1 pm to 0.2 pm. It proved that the stripelike contrast arises from a periodic chemical inhomogeneity of the synthetic crystals. The chemical inhomogeneity probably consists in periodic deviations from the stoichiometric composition of Hg,Cl,. By reason of the orientation on { llO}-, (001)-, and { 214) faces a reconstruction of arrangement of the structures in the crystals is carried out. According to that, the stripes have to be interpreted as intersection lines of 2-dimensional formations with the corresponding faces.