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Pt NPs have attracted much attention because of their applications in many aspects such as the electronics industry, fuel cells, cancer therapy, etc. The influence of the applied electric field on the formation of platinum NPs by laser (Nd:YAG, λ = 1064 nm) ablation technique was investigated, for the first time. The TEM images showed that at higher values of the electric field, a variety of shapes like rectangular, hexagon, and rhombic were appeared besides the spherical NPs, as confirmed by SEM investigations. By increasing the applied electric field, the average size of Pt NPs decreased from 20 to 9 nm. In addition, from the XRD spectra, the mean crystalline size, crystal structure, d-spacing, and lattice parameters of NPs were calculated. On the basis of the optical absorption spectra of NPs, we observed a size-dependent blue shift of the SPR peak position when the value of the electric field increased from 0 to 20 V/cm. To identify the stretching and bending frequencies of the molecular functional groups attached to the NPs surface, Raman and FT-IR spectroscopy was applied.

The amorphous W/WN bi-layer with excellent thermal stability was successfully prepared by hot-filament chemical vapor deposition method on SiO2/Si substrate. It was found that the W/WN bi-layer is technological importance because of its low resistivity and good diffusion barrier properties between Cu and Si up to 700 °C for 30 min. The thermal stability was evaluated by X-ray diffractometer (XRD) and scanning electron microscope. The XRD results show that the Cu3Si phase was formed by Cu diffusion through W/WN barrier for the 800 °C annealed sample. The formation of the Cu–Si compounds denotes the failure of the W/WN diffusion barrier with rapid increase in sheet resistance of the film. The microstructure of the interface between W/WN and Cu reflects the stability and breakdown of the barriers. The failure of this amorphous barrier occurs with heat treatment when the deposited amorphous barrier material crystallizes. The major part of Cu diffusion in polycrystalline structure with disordered grain boundaries is controlled by grain boundaries. AFM results indicated a rapid increase in surface roughness at the diffusion barrier failure temperature. It was found that the grain size plays an important factor to control the thermally stability of the W/WN bi-layer.