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Self-management and other employee involvement programs are emerging due to pressures from global competition and organizational innovations. In an organization with self-managed work teams, workers are encouraged to participate in the decision-making process pertaining to practically all aspects of management. This set-up, however, creates a problem for companies that still subscribe to traditional human resources management (HRM) practices. Given the redefinition of the role of workers, it is suggested that a paradigm for HRM reflective of this change be developed. Some possible changes that may be introduced to nine key HRM functions are discussed.

Diamond nanopillars with diameters of 1 μm down to 50 nm have been fabricated from two types of diamond thin films, namely nanocrystalline diamond (NCD) and ultrananocrystalline diamond (UNCD) using electron beam lithography (EBL) and reactive ion etching (RIE) in an inductively coupled oxygen plasma (ICP). Aim of the study was to investigate the suitability of these pillars to incorporate nitrogen-vacancy (NV) color centers for applications in quantum information technology (QIT). The first part of the investigation is devoted to a characterization of the pillars, their shape, size, and properties. The second part of this investigation concerns the optical properties of NCD and UNCD nanopillars and the incorporation of NV centers within them. Among others, fluorescence mapping and photoluminescence measurements have been employed for this purpose. It turned out that NCD pillars are quite promising for the applications in QIT envisioned. At the present time, the opposite is the case for UNCD pillars. The reasons for these differences will be discussed on the basis of the differences of the two materials NCD and UNCD. [ABSTRACT FROM AUTHOR]

Abstract: Ultrananocrystalline diamond/amorphous carbon composite films have been deposited by microwave plasma chemical vapour deposition from 17% CH4/N2 mixtures at 600 °C. Thereafter the films were subjected to various treatments (plasma processes, UV/O3 exposure) to obtain hydrogen, oxygen, and fluorine terminated surfaces, which then have been characterized with respect to their composition, roughness, wettability, and other properties. Among others, it will be shown that H- and F-terminated surfaces are very stable even if exposed for long time to air, while O-terminated ones are prone to contaminations. H- and O-termination can be patterned by applying the UV/O3 treatment through a mask. Finally, it will be shown that a non-fouling poly(ethylene glycol) layer can be grafted directly on oxygen terminated surfaces by an atom transfer radical polymerization process using α-bromoisobutyryl bromide as an initiator. [Copyright &y& Elsevier]

Tantalum pentoxide thin films have been deposited at room temperature by (dual) ion beam sputtering for applications as waveguides in biosensors. The oxygen partial pressure and the energy of the substrate ion beam were the major parameters varied in ion beam sputtering and dual ion beam sputtering experiments, respectively. For sufficiently high oxygen partial pressures, the films were stoichiometric, free of contaminants, amorphous, and extremely smooth. Ion bombardment of the growing films with Ar+ ions up to 200 eV had no significant influence on these properties. The refractive index of stoichiometric films was 2.1±0.1 and the extinction coefficient well below the resolution limit of ellipsometry and UV/visible measurements. By coupling a laser beam via an optical grating into a 150 nm thick Ta2O5 layer, the optical losses could be estimated to be below 3 dB/cm. A series of experiments has been carried out to prove that this deposition process is compatible with the use of thermoplast substrates which are sensitive not only to high temperatures but also to ion bombardment and UV radiation. Finally, first experiments are presented to functionalize the surfaces of Ta2O5 films with amine and epoxy groups. [ABSTRACT FROM AUTHOR]

Abstract: The surfaces of nanocrystalline diamond/amorphous carbon (NCD/a-C) nanocomposite films deposited from a 17% CH4/N2 mixture have been subjected to a variety of plasma and chemical treatments, namely H2 and O2 microwave plasmas, a CHF3 13.56 MHz plasma, and a chemical treatment with aqua regia (HCl:HNO3 3:1). The resulting surfaces have been studied with respect to their chemical nature by X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (TOF-SIMS), concerning their morphology with atomic force microscopy, and by contact angle measurements to study their hydrophobicity and their stability. As-grown surfaces are hydrogen terminated, but the number of C–H bonds can slightly be increased by a H2 microwave plasma, while treatment with aqua regia considerably lowers the number of C–H bonds at the surface. O2 and CHF3 plasmas, on the other hand, lead to a replacement of the terminating C–H bonds by C–O or C–OH and C–F x groups, respectively. Finally, by contact angle measurements over a period of 150 days it could be shown that the H-terminated surface is very stable whereas the contact angle of the O-treated surface changed considerably with time, probably due to the adsorption of contaminants. [Copyright &y& Elsevier]

Abstract: Nucleation and growth, but especially the development of the morphology of nanocrystalline diamond/amorphous carbon (NCD/a-C) nanocomposite films have been investigated by systematic variation of three important parameters, namely the deposition time, the growth rate, and the substrate pre-treatment used to enhance the nucleation density. The films have been characterized, among others, by scanning electron microscopy, atomic force microscopy, and Fourier transform infrared spectroscopy. It is shown that, by successive addition of ultradispersive diamond powder to the suspension of nanocrystalline diamond powder in n-pentane used for the ultrasonic pre-treatment, the nucleation density can be enhanced by two orders of magnitude from 1·108 cm−2 to >1·1010 cm−2. This reduces the thickness required to achieve closed films from 1 µm to 100 nm. However, once coalescence of the individual nodules emerging from the nucleation sites has taken place the films loose “memory” of the nucleation step and start to develop the typical NCD morphology consisting of larger features with diameters of some hundreds of nm which are in turn composed of much smaller features. Irrespective of the feature size and of the parameters used, the films of this investigation possess AFM rms roughnesses of 9–13 nm, indicating that rms values are not sufficient to characterize NCD surfaces. [Copyright &y& Elsevier]

Tantalum pentoxide (Ta2O5) thin films have been deposited by reactive ion beam sputtering at room temperature. The films have been characterized by scanning electron microscopy, atomic force microscopy, x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), variable angle ellipsometry, and UV-VIS spectroscopy. The main parameter varied was the oxygen partial pressure. Stoichiometry is reached for pO>=3×10-2 Pa; within the limit of XPS (∼1%) the films are free of contaminations. They are extremely smooth with a surface roughness of 0.14 nm only. From FTIR, it can be concluded that they are amorphous. For stoichiometric Ta2O5 films, the refractive index at 532 nm is in the range from 2.05 to 2.2, while the extinction coefficient is below the detection limit of our ellipsometer. UV-VIS spectra show stoichiometric films to possess a high transmission in a wide wavelength range with an absorption edge below 300 nm. [ABSTRACT FROM AUTHOR]

Abstract: Nanocrystalline diamond/amorphous carbon (NCD/a-C) nanocomposite films have been deposited by microwave plasma chemical vapour deposition (MWCVD) from CH4/N2 mixtures. The films have been thoroughly characterized by a variety of methods with respect to their composition, morphology, structure and bonding environment. Thereafter, the bioproperties of these films have been investigated. Tests with osteoblast-like cells and pneumocytes proved that the NCD/a-C films are not cytotoxic. In addition, exposure of the films to a simulated body fluid revealed that they are bioinert. Further experiments addressed the question whether biomolecules such as RNA or proteins bind unspecifically on the surfaces of NCD/a-C films. By means of atomic force microscopy (AFM) and scanning force spectroscopy measurements it was established that, in contrast to control experiments with mica and glass, no interaction between the nanocrystalline diamond and either RNA or protein molecules took place. The results of these experiments concerning the biologically relevant properties of NCD/a-C films are discussed in view of possible future applications, e.g. as a material for the immobilization of biomolecules and their characterization by AFM measurements and related techniques. [Copyright &y& Elsevier]

Thin nanocrystalline diamond/amorphous carbon (NCD/a-C) composite films were prepared by microwave plasma chemical vapor deposition (MWCVD) from methane/nitrogen gas mixtures. The investigation of the basic films properties (crystallinity, morphology, composition, structure, etc.) showed that the layers are composed of diamond nanocrystallites with a size of 3-5 nm, which are embedded in an amorphous carbon matrix. The ratio of the two fractions in the composite films is close to unity. Here, we report on the characterization of these films with regard to their optical properties and compare them with those of polycrystalline diamond (PCD) films also prepared by MWCVD. Optical reflectivity and total light scattering were measured in the range from 200 to 1000 nm using a spectrophotometer, while a null-type ellipsometer was used for the ellipsometric characterization of the samples. The measured spectra were mathematically simulated in order to obtain the refractive index and the extinction coefficient. The NCD/a-C films have refractive indices between 1.8 and 1.9 in the visible region; their extinction coefficient increases from the IR to the UV region, reaching a value of about 0.1. In case of PCD films, the refractive index varies between 2.1 and 2.3 due to dispersion, while the extinction coefficient is close to zero in the whole measured spectral range. Finally, the optical characteristics are correlated with the basic film properties (topography, structure, nature of the matrix, etc.). [ABSTRACT FROM AUTHOR]

Abstract: Nanocrystalline diamond (NCD) films in an amorphous matrix have been deposited by standard microwave plasma chemical vapour deposition from CH4/N2 mixtures, and subsequently characterized comprehensively with respect to their structure and morphology, their composition, their crystalline properties, and their bonding environment. Thereafter, some of the coatings have been subjected to rapid thermal annealing (RTA) at 1100 and 1400 °C, respectively. Characterization of the annealed films by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR) revealed the loss of material upon annealing, while the bonding structure remained almost unchanged at least after the 1100 °C treatment. RTA at 1400 °C leads to the formation of crystalline SiCxNyOz material, very probably by reaction with the residual gas, whereas crystalline graphite is not observed. FTIR measurements indicate that hydrogen containing species from the residual gas may contribute to the loss of material. Finally, the morphological changes observed after the annealing give some insight into the growth mechanisms of these NCD films which are discussed in terms of a spherulitic growth caused by a rather low primary nucleation density but very high secondary nucleation rate. [Copyright &y& Elsevier]