The anode layer source is a relatively poorly known technique which has so far been mainly used for etching of surfaces. In correct conditions, however, it can be also used for deposition of diamond-like carbon films. We investigated the influence of deposition parameters on the structure and composition of films. For this purpose we applied three techniques: elastic recoil deflection analysis, Rutherford backscattering spectroscopy and Raman spectroscopy. We found out that the structural ordering increases both with discharge voltage and nitrogen flow. The hydrogen concentration is about 20 at.%, it gently decreases with nitrogen flow, but does not change with other parameters.
COBISS.SI-ID: 26216999
Based on examples of several hard coatings we showed the applicability of four techniques for analysis of growth defects, which form during coating deposition. Three of them use SEM microscopy on samples prepared in different ways: (i) on a fracture, (ii) on a specially prepared local cross-section, using the focused ion beam, (iii) on a crater prepared by glow-discharge optical emission spectroscopy. We analyzed the suitability of these methods for identification of defect formation and growth. Using the third method, 3D surface profilometry, we performed a statistical analysis of the defect density and identified its dependence on deposition parameters.
COBISS.SI-ID: 25571623
To study phase formation up to 2300 K, tungsten carbide–cobalt (WC–Co) samples were exposed to concentrated solar radiation in hydrogen plasma. The results showed the appearance of Co6W6C phase at the temperature of 1050 K. This phase almost vanished at the temperature of 1300 K and was replaced by the Co3W3C phase. This phase vanished at1690 K where only WC and Co peaks were detected by XRD. The AES depth profiles showed enrichment of the surface film with Co at elevated temperatures. At extremely high temperature of 2300K, the Co vanished from the surface layer but remained in crystalline form in the bulk material. SEM imaging showed an evolution of the material crystallinity up to perfectly recognizable crystals of the dimension of approximately1 micrometer at the maximum temperature.
COBISS.SI-ID: 26109991
We compared the effects of 200 keV Ar and 166 MeV Xe ion irradiation on immiscible AlN/TiN multilayers in order to study ion interactions, atom mixing at interfaces and formation of instable phases. In case of Ar implantation both atomic collisions and electronic excitations contribute to the induced structural modifications, and in case of Xe only electronic excitations. Thermal spikes, developed both in Ar implantation and Xe irradiation, lead to lateral grain growth in individual layers. The results can be interesting towards developing radiation tolerant materials.
COBISS.SI-ID: 25676839
Thin film deposits of carbon and tungsten likely to be formed in advanced fusion reactors with W and C divertors were exposed to highly dissociated hydrogen plasma created by a microwave discharge at the power of 1000 W. Some samples were heated additionally by concentrated solar radiation. After plasma treatment, the samples were characterized by X-Ray Diffraction and Auger Electron Spectroscopy. The results showed that aggressive hydrogen plasma allows for the removal of carbon from the deposits at moderated temperatures. Prolonged treatment showed formation of highly crystalline pure tungsten so the technique is suitable for selective removal of mixed deposits formed in fusion reactors.
COBISS.SI-ID: 25951015