Karol Kyzioł

Stability of a-C:N:H Layers Deposited by RF Plasma Enhanced CVD

A series of amorphous hydrogenated carbon layers doped with nitrogen (a-C:N:H) was deposited on Si (001). The synthesis was performed from gaseous N2/CH4 mixture using PE CVD (RF CVD technique; 13,56 MHz). An influence of the processing conditions on layer-growth rate was analysed. Thickness of the layers deposited during 1 hour at various temperatures, pressures and RF powers were taken as a basis. It has been proved that the substrate temperature is a key parameter for the layer formation. Temperature rise results in the deposition rate decrease. This unfavourable effect may be reduced by application of increased gas pressure and/or higher plasma RF generator power. At optimal conditions (46 oC; 0,8 Tr; 60 W) the deposition rate reaches up to 600 nm/hour. FT-IR spectra of the layers were measured within 1250 - 4000 cm-1 and discussed with regard to the atomic structure. The intensities of the characteristic absorption bands were compared. The results show that the layers have various N/C ratios according to the applied processing conditions.

Surfaces Modification of Al-Cu Alloys by Plasma-Assisted CVD

Aluminum-copper alloys (Al-Cu) are nowadays widely used in various applications, mainly in automotive and aviation industry, because of their unique properties such as high strength, low density and good corrosion resistance. However, usages of aluminum alloys are partially limited due to their reduced hardness, wear resistance and poor tribological parameters. Desired useful parameters can be improved by application of PA CVD technology. This work presents the results concerning determination and analysis of the structure and the selected properties of the modified surfaces of Al-Cu alloys (2xxx series) that were prepared using plasma assisted MW CVD (Micro-Wave Chemical Vapour Deposition) method. To ensure effectiveness of the substrate modification process, the covered surface was subjected to pre-treatment with argon plasma and/or nitriding process. In conclusion, the research has confirmed that the wear resistance of the Al-Cu alloy can be successfully modified by application of MW CVD technique. The obtained results can serve as a basis in the design of the technology of a-Si:C:N:H layers for diverse applications.

Chapter 4 – Surface Functionalization With Biopolymers via Plasma-Assisted Surface Grafting and Plasma-Induced Graft Polymerization—Materials for Biomedical Applications

Abstract Engineered biomaterials have revolutionized current medicine significantly, expanding the range of tools offered even for theragnosis. Such innovative systems find various practical applications in cancer therapy and diagnosis, bacterial infections treatment, acceleration of wound healing, etc. Basic surface chemistry methods coupled with advanced physiochemical modification produce innovative hybrid coatings for both metallic and polymeric substrates. In particular, plasma-assisted chemical grafting methods enable surface functionalization of biomaterials providing covalent bonds between the substrate and the polymer monomers. These thermodynamically stable layers with high energy bonds offer the possibility to obtain advanced hybrid systems for various medical applications, including drug delivery systems. The current state of the engineered systems based on plasma-induced grafting biopolymers and promising new research directions for orthopedics, implantology, tissue engineering, wound regeneration and infections control, as well as production of medical devices will be identified and reviewed.