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The potential of pulsed laser deposition in an applied uniform electrostatic field was investigated. A flat, positively charged, fine-celled-grid counter electrode was used to provide bias voltage of up to +50 kV with respect to the substrate. This enabled control of the atomic mixing and made it possible to initiate chemical bond formation at the interfaces of the films formed by deposition from the laser-induced plume. As an example, the results of multilayer 56Fe/MoSx/57Fe film deposition are presented. At first, a bilayer MoSx/57Fe film was grown in the absence of the electric field. This was followed by 56Fe film deposition in an applied field. A relatively sharp interface between the MoSx and 57Fe films was observed. In contrast, after 56Fe deposition, effective atom mixing was observed and new chemical bonds between Fe, S and Mo were detected. By penetrating through the interface, accelerated 56Fe ions gave rise to the growth of an amorphous layer of up to 50 nm in thickness. It consisted of rather evenly distributed Fe, S and Mo atoms (at total ion dose of 2.5×1016 cm−2). The ion flux destroyed MoS chemical bonds, and the S atoms released preferably bound Fe atoms, thus forming a FeS2-type phase. The Mo atoms, as a lower-oxidation-state species (apparently together with S atoms), were localized in the vicinity of Fe atoms and affected the hyperfine magnetic fields. The technique developed has made it possible to study the ion-induced processes occurring at the interfaces of multilayer films. It can also be applied to improve the tribological functionality of thin films.

Hard, adherent amorphous carbon films were formed by condensation of evaporated carbon particles with additional noble gas ion bombardment of the growing film (ion assisted evaporation (IAE)). Ion energy, ion mass, angle of ion incidence and ion-to-atom arrival rate are the main parameters influencing the film growth. The effects of these parameters on the resulting structural (electron energy loss spectroscopy and density determination) and mechanical (Vickers hardness measurements) film properties were studied. In addition, a systematic investigation of the corrosion protection potential of the carbon IAE films was carried out. It could be shown that the corrosion protection and the hardness of the films are strongly dependent on the angle of ion incidence and the ion-to-atom arrival ratio. The latter quantity and the ion energy also affect the film density and structure. The experimental results are discussed in the context of simulations of ion-atom interactions. In general, the depth and volume of the activated region and the amount of transferred ion energy to the carbon matrix atoms mainly affect the film growth and the resulting film properties.

Amorphous carbon layers (a-C, a-C:H) with a hydrogen content between 3 at.% and 25 at.% were deposited by plasma decomposition processes, sputtering and evaporation. Their mass density values were obtained from a flotation method. The refractive index and absorption coefficient were calculated from spectrophotometric data. Special attention was paid to the Urbach tail and Tauc's plot absorption regions. The electrical conductivity was investigated in the temperature range T = 80–350 K. The conductivity values of all types of layers are discussed in terms of thermally activated conduction processes. In this sense all layers behave like semiconductors. For interpreting the conductivity values of the high gap layers, a Davis-Mott model with broad band tails was applied. However, this model was insufficient for fitting the conductivity data of samples with vanishing gaps. Reproduction of the conductivity values of these layers was possible in terms of a band model considering a structureless band at a position of 10–50 meV above the Fermi level. The conductivity of low gap samples (optical gaps around 0.3 eV) could only be fitted by a superposition of the conductivity laws following from both models. Fortuitously, the superposition of these functions yields a temperature dependence very similar to Mott's T − 1 4 law between 50 K and 300 K, which may be an explanation of this widely observed behaviour.

In depositing thin carbon films by the r.f. sputtering of a graphite target in argon, an optimal parameter window was found in which it is possible to prepare adherent, IR-transparent, insulating, hard layers. Approximations for the sputtering process (total sputtering yield, energy of the sputtered carbon particles on the substrate) are demonstrated. A characteristic dependence of the film properties on the target voltage, an essential sputtering parameter, exists. In all cases, the target voltage influences the bombardment of the growing film by charged energetic particles. An anisotropic layer behaviour was established for more strongly absorbing films by three different methods of investigation. Finally, preliminary considerations concerning the film structure were made.

A new method for optical thin film constant determination from spectrophotometric data is presented. The method combines features of single-wavelength methods as well as multiwavelength methods and thus represents a hybrid method specially designed for the analysis of amorphous thin film materials with more or less involved absorption behaviour, such as amorphous hydrogenated carbon (a-C:H), amorphous hydrogenated silicon (a-Si:H) and related materials. The unambiguity and continuity of solution contours are guaranteed without the postulation of any analytical dispersion law, by introducing specially constructed mathematical terms into the merit function to be minimized. The accuracy in determining refractive indices and film thicknesses is comparable to that achieved by curve-fitting methods. Weak inhomogeneities in film thickness may be taken into account.

The optical parameters n and k of i-C:H layers produced by microwave plasma deposition and from an ion-plating deposition system on silicon substrates are determined by T and R measurements in the IR range. A computer model is given; the multiple solutions, the influence of errors in experimental values and the absorption peaks of the i-C:H layers in the IR range are discussed.

The growth of device-worthy silicon crystals on insulating substrates would offer a new type of semiconductor technology. Lateral epitaxial growth is demonstrated for several types of structures using island configurations of silicon deposited either onto continuous or onto structure-etched SiO 2 . The crystallization of the deposited silicon islands was performed either by a large-area light pulse or by a zone melting process. With regard to the crystallinity and the flatness the best results were achieved using encapsulated island structures and the zone melting process.

The deposition of hydrogenated amorphous carbon films by an electron cyclotron resonance (ECR) microwave plasma and an ECR microwave ion beam source is described. Optical, electrical and mechanical measurements and different analytical methods are used for film characterization. The films deposited at a rate of about 200 nm min-1 develop a high electrical resistivity (109-1014 Ω cm), good IR transparency, an optical gap of about 1.7 eV and a hardness up to 30 GPa (measured on silicon substrates). Sputtering deposition experiments were performed with the aim of investigating the influence of the hydrogen on the layer properties as well as the possibilities of deposition on highly insulated substrates. Layers made by means of the sputtering deposition method indicated that hydrogen might be involved in the set-up of a metastable ion-assisted hydrogenated amorphous carbon.