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One of the main specific features of the cold spray process is localisation during particle impact deformation. The resultant adiabatic shear instability is the phenomenon that is known to play a major role in the particle/substrate and particle/particle bonding and coating structure formation during the cold spray process. In this article, the cold spray process is numerically simulated as an impact between a single spherical particle with the substrate, and comparison with experimental results for Armco iron and stainless steel particles is made. To describe a deformation behavior of the two materials at high strain rates, the Johnson–Cook model has been chosen. The results indicate that the model accurately captures the grain distortion in the impact zone for both materials. This approach provides valuable information on the characterisation of the strain localisation at the particle/substrate interface.

The present work considers simulation of contact area formation using the contact models of Hertz, DMT and JKR. The purpose of this work was to study development of real contact between rough surfaces taking into account the action of adhesion. The model of the Winkler foundation is used to describe the elastic properties of the rough surface. Solids with thin hard coatings were used as test specimens. The surface topography was measured with typical AFM at different scale levels. The data on the specific surface energy of specimens are obtained with contact adhesion meter developed in MPRI (Gomel, Belarus). The obtained value of specific surface energy was used in computer simulations of real contact using the AFM images.

Numerous studies attest to the cross language differences that have lead to important advances in understanding how language is processed and which have important implications for clinical and educational issues. One area that has been largely neglected concerns speaking fundamental frequency (SFF). It is well known that SFF differs across languages, but to date few studies have examined SFF in bilingual speakers. We investigated SFF in 12 highly fluent bilingual female speakers and 12 matched monolingual speakers for each language (12 in German, 12 in English). Electroglottographic measurements were made from samples of spontaneous speech (relating a joke) and reading. The SFF of the monolingual English vs. German speakers differed significantly (ANOVA p=0.001) from each other. The SFF of the bilingual speakers differed significantly according to which language they were speaking (p=0.008), with English higher. They also differed significantly in both languages from the monolingual comparators (p=0.001 for both languages), with values between the two monolingual groups. We discuss the results in relation to sociocultural and forensic issues as well as in relation to voice diagnostic and therapeutic implications and lessons for second language acquisition.

Chemical reactions between small carbon molecules up to C5 in rapidly expanding pure carbon vapour are considered under the assumption of translational equilibrium. The equilibrium between translational and internal degrees of freedom of molecules (vibrations and rotations) is not implied. To take into account the difference between the translational and internal temperatures, the conventional equations of chemical kinetics are complemented with energy balances. Numerical calculations are made for the expansion dynamics, typical for graphite ablation by 25 ns laser pulse at the target temperatures from 2500 to 6000 K. The translational part of internal energy of vapour rapidly decreases at expansion and a large gap between translational and internal temperatures arises after about 10 −6 –10 −5 s. Translational temperature becomes very low and internal

The tribological performance and tribochemistry of both single-layer WSex(Ni) and bilayer WSex(Ni)/diamond-like carbon coatings formed on steel substrates by pulsed laser deposition are evaluated. The ball-on-disk tests of the coatings in air show that at a laser fluence of ∼100 J cm−2 and a partial pressure of argon ∼2 Pa, the endurance of the top WSex(Ni) film in the bilayer coating is nearly four times greater than for single-layer WSex(Ni) film. For the top WSe2(Ni) layer 170 nm thick, deposited onto DLC coating 200 nm, the coating friction coefficient was kept 0.03–0.09 during nearly 2 × 104 cycles.

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.

The results of comparative measurements of annihilation rate coefficients of fluorine radicals (Ka) are presented. These results are obtained by means of three modifications of time-resolved actinometry: 1. by conventional techniques with square pulse delay time variation in a full discharge power modulation mode; 2. with partial discharge power modulation by square pulses; and 3. with full discharge modulation by a series of short pulses in the afterglow stage. Intensity microchronograms of spectral lines of F radicals (703.7 nm), Ar (750.4 nm) and their background values (701.7 and 748.4 nm) were obtained by means of a dedicated time-resolved (2.5 μs) acousto-optic spectrometer. The spectral resolution was equal to 0.35 nm. Fluorine radicals' kinetic annihilation curves were deduced by processing the measured chronograms according to the basic actinometry equation. Ka values were determined from exponential decay fits of the dropping parts of the kinetic curves. In addition, in the first of the above-mentioned modifications, a residual concentration level was used in an integral expression for the reactive particle concentration at the annihilation stage. The importance of this parameter was shown in earlier papers.

A method of emission actinometric measurement of kinetic parameters of plasmachemical reactions is proposed including the determination of the kinetic order, annihilation rate constants of chemically active particles and their characteristic lifetimes. The basis of the method is the time-resolved actinometry and the discharge power modulation by a probing pulse series at the afterglow stage with a time resolution of Δ t ≥1 μs. Kinetic accumulation and annihilation curves at this stage are derived from the microdynamics of spectral line intensitities of the selected actinometric pairs. The measurements of spectral line peaks and their background values controlled by the PC microcomputer are carried out at four to nine wavelengths in a quasi parallel mode of an acoustooptic spectrometer. The duration of a measurement cycle of 100 repeated measurements at four wavelengths with a time resolution of 25 μs took no more than 50 s. The values of kinetic parameters can be derived from the analysis of the logarithmic plot of the kinetic curve of particle annihilation. Measurements of the heterogeneous annihilation rate constant for atomic fluorine have been carried out in the SF6 RF plasma with an addition of argon as an actinometer in a standard diode-type Al-reactor. The values of pulse length and duty cycle of probing pulses are determined experimentally for measuring the kinetic parameter of fluorine annihilation in such a way that there is no substantial increase of the fluorine residual concentration level. Based on the analysis of the experimental kinetic curve of heterogeneous annihilation, a solution taking into account a procedural error of the proposed method due to nonzero level of the residual concentration of the observed particles at the afterglow stage is proposed. The experimentally obtained value of the fluorine heterogeneous annihilation rate constant measurement error is about (15±2)% at a residual concentration level of about 10%. The measurement reproducibility of fluorine heterogeneous annihilation rate constant is 3–5% in the unloaded and silicon wafer loaded reaction chamber with actinometer concentrations of 2.5 and 5.6%.

Spectral investigations were carried out in a plasma-enhanced chemical vapour deposition (PECVD) process using hexamethyldisiloxane (HMDSO) thin film deposition. The experiments were performed in a closed reactor with r.f. plasma generation in the pressure range of 20–40 Pa and power range of 10–20 W. It is shown that the emission lines of atomic hydrogen (486 nm) and CH radicals (431 nm) are the most informative lines from the point of view of the process dynamic control, because hydrogen is the final product of the discharge and CH is an indicator for the last intermediate products (CxHy) of the process obtained. Other species (Si and O) are built in the deposited coating. The excitation energy of the hydrogen lines (≈ 12 eV) permit the use of the argon emission line at 750 nm as an actinometer (≈ 11 eV ). A problem for using actinometry is the large difference of the exciting level of the CH band (≈ 3 eV). That is why in the following article is shown as only a first approximation for characterising this PECVD process. By adding argon (up to 10%) the process dynamic was controlled in the hydrogen and CH radicals concentration measurement mode. The measurement was realised by using spectral signals measured at 5–8 (peak and its background) different wavelengths in the quasi parallel mode of an acoustooptical spectrometer. The measured curves of the relative H and CH concentrations demonstrate the CH accumulation due to plasma chemical conversion of HMDSO during the first two stages of the process duration. The final stage of the process is characterised by the dissociation of CH radicals, which results in a synchronous increase of the hydrogen signal and decrease of the CH radicals signal causing the existence of free carbon, which appears as carbon enriched coverage on reactor walls.

The solution is proposed to the problem of the relative concentration dynamics control of chemically active particles in the low temperature gas plasma as well as the investigation of their generation and annihilation by means of time-resolved actinometry. A special small-size acousto-optic spectrometer has been constructed capable of spectral resolution of 0.1–0.3 nm in the visible range (430–850 nm) and the maximum time resolution of 2.0 μs. The software package developed allows: 1. (1) measuring of the chronograms of the relative concentrations of various active particles in parallel mode at eight spectral channels; 2. (2) generating impulse plasma modulation and measuring the microdynamics of the generation and annihilation of the active particles in the frame-by-frame mode (1024 points) in four parallel spectral channels, including the two corresponding background values. To shorten the measurement time and to improve the measurement accuracy of the particle annihilation kinetic characteristics in the interval between two stationary (long) pulses, it is proposed to form a series of probing (short) pulses. Some preliminary results are presented of the monitoring of the fluorine radicals (703.7 nm) relative concentration in the SF 6 gas r.f. plasma, containing as an actinometer a small amount (up to 5%) or argon (750.4 nm) at different discharge powers. Using the measurement results of the fluorine radicals, relative concentration in the pulse-modulated noble gas plasma obtained at monosilicon etching, the constants of the radical accumulation, as well as their life time values, are determined for the loaded and unloaded reaction chamber.

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.

Even 100 years ago the problem of quality assurance in anaesthesia was investigated. In 1890 the German Society of Surgery decided to start "Multicenter Statistics on Surgical Anaesthesia." The project was headed by Ernst Gurlt, surgeon in Berlin. In 1893 he reported on the basis of 62 questionnaires on approximately 50,000 anaesthetic procedures, mostly performed with chloroform. 9 fatal chloroform cases led to a mortality rate of 1:4,275. On the other hand among 6,213 cases with ether anaesthesia there was no death. Gurlt strictly recommended the administration of ether, seconded by contemporaries such as Garre, Trendelenburg, Roux and Juillard. Gurlt's report includes as appendix detailed information on the administered anaesthetics, application techniques, premedication, fatal and non-fatal complications extracted from 18 of the analysed questionnaires. Gurlt's publication is an early document of quality assurance in Germany.

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.

The optical constants of fine-grained diamond layers have been investigated by spectrophotometric means in the near-IR and visible spectral ranges. The layers were deposited by a microwave chemical vapour deposition technique on 〈100〉 and 〈111〉 oriented silicon substrates. For determining the optical parameters, measurements of the directed and diffuse reflectance and transmittance of the layer-on-substrate system have been carried out. The calculation of the optical constants has been accomplished by a curve-fitting procedure. For that purpose, a quadratic error function has been minimized by the method of conjugated gradients. To reduce the multiplicity of solutions, the refractive index has been assumed to increase with increasing wavenumber following a quadratic dispersion law, while the loss coefficient is assumed to increase exponentially with increasing wavenumber. The investigation of experimental spectra has shown that the method works successfully in application to layers with a surface r.m.s. roughness less than approximately 100 nm. For such layers, refractive index values have been obtained which are slightly lower than those of natural diamond, while the loss coefficients are much higher because of surface and bulk scattering.

The preparation of polycrystalline diamond particles and thin diamond films by deposition in the plasma discharge of a hollow cathode arc has been investigated. Although this discharge is known as a very simple and effective system for plasma generation, there has been little information about the growth of diamond by means of this method up to now. This type of discharge combines thermal and plasma dissociation of the reactant gases for diamond deposition. The temperature of the deposition area can be easily controlled by the electron current to the substrate and thus no auxiliary heating system is required, in contrast to many other diamond deposition methods. Furthermore, we assume additional decomposition of the reactant gases at the surface of the substrate due to the strong electron bombardment. As-deposited diamond particles and films were investigated by various electron microscopy methods, Raman spectroscopy and optical methods. They clearly show a polycrystalline structure with good crystallinity and quality. The diamond growth rate reaches about 2 μm h−1 on a deposition area of about 4 cm2.

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.

The optical properties of hard dc plasma deposited amorphous carbon layers have been investigated from the middle IR up to the visible spectral region. Refractive indices and absorption coefficient behaviour have been determined by means of spectral transmittance and reflectance measurements. The layers show a transparency window in the middle IR in the wavenumber range 1700 cm −1 v −1 . The refractive indices in the “window” region are between 2.1 and 2.3 with weak dispersion. IR-absorption losses have been discussed in terms of a dispersion model, considering the absorption detected to be caused by a superposition of Lorentz-lines and an Urbach-part. Planar and transverse conductivities of the layers have been determined at room temperature. In addition, the conductivity of representative samples has been investigated in dependence of the temperature in the range of 80 K up to 350 K. A correlation between the thus-obtained activation energies for thermally-activated hopping in the band tails and the Urbach parameters of the layers could be established.

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.

Modern trends in miniaturization of components cause the necessity of evaluation of tribological characteristics at conditions close to real operation. Existing methods and equipment such as AFM cannot give the adequate data on tribological performance of tiny tribounits, because the test contact loads, sliding velocity, and contact areas are not similar to real ones. The presentation describes the design and test data when using laboratory equipment for measuring adhesion forces and friction properties of micro systems. The set of developed devices includes adhesion meter, rotary and reciprocating microtribometers.

A novel arrangement for the production of a microwave plasma by electron cyclotron resonance is described. Ion currents with current densities of up to 2.5 mA cm−2 can be homogeneously extracted from the plasma over surfaces having diameters of up to 10 cm. The microwave plasmatron can be operated by various working gases. Its application in the deposition of hydrogenated amorphous carbon (a-C:H) layer has been investigated. At a high deposition rate (200 nm min−1), a-C:H layers were deposited presenting properties which were also obtained by other workers who applied different techniques.

Amorphous hydrogenated carbon films were prepared in an inductively-coupled 13.56 MHz r.f.-glow discharge. The C2H2 pressure varied between 4 × 10−4 mbar and 8.2 × 10−3 mbar. The average ion energies were in the range of about 30–350 eV. The films were characterized by measuring the hardness, stress, density and hydrogen content. Additional investigations were made by visible ion spectroscopy-infrared spectroscopy, electron energy loss spectroscopy and electron diffraction. Magnetic resonance methods like 13C nuclear magnetic resonance and electron spin resonance have been used to determine the ratio of sp2- to sp3-hybridized C atoms and the spin density.

In the present study mass spectrometric measurements were carried out on the ion flux to the substrate during the a-C:H deposition process by ion plating and r.f. glow discharge. For this purpose a portion of ion flux striking the substrate was passed through an aperture into a differentially pumped chamber, in which the energy distribution of the ions is measured by an electrostatic analyser and the e/m value by a quadrupole mass spectrometer. The discharge conditions were measured with a Langmuir probe. Depending on the discharge conditions and the hydrocarbon gas used, typical ion groups are observed. These ion groups are generated by electron impact or ion-molecule reactions.

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 present work was undertaken to study tribo-induced chemical and structural changes occurred in the MoSe(Ni)/a-C antifrictional coatings formed by pulsed laser deposition under varied conditions. The influence of these parameterson the wear resistance of the coatings was investigated.Keywords: molybdenum selenide, diamond-like carbon, laser deposition, friction, multilayered coatings 1. INTRODUCTION Transition metal dichalcogenide (TMD) films are very promising for solid lubrication. Up to date the tribological functionalities of both MoS2 and WS2 -based coatings are thoroughly investigated. At the same time MoS and WS,,components are used in the coatings of different architecture: 1) single-layer TMD coating" 2;2) combined TMD/hard ceramics double-layer coatings" ' 4; 3) multi-phase composite coatings, containing nanocrystalline TMD5' 6 Molybdenum and wolfram disulfides show the exceptional tribological properties in vacuum and in the inertenvironment. However, their tribological behavior is essentially worse in the oxygen-containing media due to their

Imaging spectroscopy is a powerful tool for visualization of plasma phenomena. A novel type of imaging spectrometer based on an acoustic optical tunable filter (AOTF) was used to select several emission lines for imaging from a mercury: rare gas glow discharge driven by direct current (dc) current. Images taken from this discharge show different locations of light origin for different emission lines. The spatial and wavelength resolutions of the spectrometer are evaluated.

The potentially wide range of optical constants obtained from differently deposited carbon layers with diverse atomic structure has been the subject of an intensive research in recent years. The optical properties are well known to depend strongly on the level of contamination and the degree of atomic order in the layer material. The purpose of the present paper is to sum up the results of our investigations of optical and electrical properties of numerous differently deposited carbon layers and to relate them to the results of measurements of mass density, the atomic composition of the layers and electron diffraction measurements. In particular, estimation formulas are provided to relate the IR refractive index to the mass density and the hydrogen concentration of the layers. In addition, special attention is paid to the exponential absorption region.

The optical properties of hard amorphous carbon layers deposited by different techniques (ECR-microwave plasma deposition, dc-plasma deposition, rf-sputtering, and electron beam evaporation) have been investigated from the middle IR up to the visible spectral regions. Refractive indices and absorption coefficient behavior have been determined by means of spectral transmittance and reflectance measurements. ECR microwave and dc-plasma deposited layers show a transparency wind w in the middle IR in the wavenumber range 1700 cm -1 -1 . The refractive indices in the window region are between 1.9 and 2.3 with weak dispersion and show the usual increase of film mass density. However, absorption losses in the window-region are considerably higher than those in the case of diamond. For dc-plasma deposited layers, IR-absorption losses have been discussed in terms of a dispersion model, considering the absorption losses detected to be caused by a superposition of Lorentz lines and an Urbach tail. RF sputtered layers represent some kind of intermediate between graphiticlike layers (deposited by electron beam evaporation) and IR-transparent carbon formations. For rf-sputtered layers, IR-refractive indices show an extraordinary dependence on film mass density, which could be explained in terms of a mixing model, considering these layers to be built from graphiticlike and polymericlike compounds.

Silicon on insulator (SOI) structures were produced by recrystallization of polycrystalline silicon deposited on thermally grown SiO2 using either a single‐flash lamp pulse or light strip scanning. In the latter case of lateral zone melting, encapsulating coatings of Si3N4/SiO2 were found to be necessary to obtain closed films. Examinations by electron microscopy revealed the formation of subgrain boundaries that can be entrained under light‐absorbing strips of Si or MoSi2. In conclusion of basic considerations concerning the stability of the system during recrystallization, a major influence of the wetting behavior at the interface between the encapsulating layer and the molten silicon was deduced, and a rough interface and/or the addition of some monolayers of carbon was found to be favorable. Measurements performed with SOI test circuits confirmed the device‐worthy quality of the films, for which first applications in optoelectronic memories have been realized.

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.

The growth of device-worthy silicon crystal films on insulating substrates would offer a new type of semiconductor technology. The crystallization of continuous silicon layers on thermally oxidized silicon wafers was performed by a zone melting process. A number of material characterization techniques have been used to analyse the SOI-structures.

The deposition of a-C:H films by an ECR microwave plasma and an ECR microwave ion beam source is described. Optical, electrical, mechanical measurements and different analytical methods are used for the film characterization. The films deposited of a rate of about 200 nm/min develops a high electrical resistance (109 to 1014ω cm), a good IR transparency, an optical gap of about 1.7 eV, and a hardness up to 30 GPa (measured on Si-substrates).

An investigation was made of the characteristics of switching and photosensitivity of a reusable optoelectronic storage medium based on planar metal–insulator–semiconductor–insulator–metal structures. Estimates indicate that data can be stored in such a medium with a density in excess of 107 bit/cm2 and the energy needed to record one bit is about 2×10−13 J.

Thin neodymium-cobalt films prepared by vacuum evaporation were examined by transmission electron microscopy and defocused Lorentz microscopy. The examined films were polycrystalline with crystallite sizes about 40 AA and possessed magnetisation ripple structure. Interpretation of ripple in the framework of Hoffman (1964) and Harte (1968) linear ripple theory is presented.