Laser Ablation Of Ceramic Target Research Articles

Synthesis of spherical zinc sulfide nanoparticles produced by femtosecond laser ablation and deposited on a silicon substrate under the action of an electrostatic field

In this paper we consider the synthesis of spherical zinc sulfide (ZnS) nanoparticles (NPs) deposited on a silicon substrate by femtosecond laser ablation of ceramic target under the action of an electrostatic field in argon gas atmosphere. The use of an electrostatic field in the process of ablative synthesis of NPs allows, in addition to capturing particles, to carry out predicted deposition of nanomaterials on the substrate, while carrying out the ablation products from the region of laser beam propagation. The morphology and structural characteristics of synthesized ZnS NPs were investigated using scanning electron microscopy and X-ray diffraction analysis. The size distribution of ZnS NPs were studied using dynamic light scattering technique. Obtained NPs have a spherical shape and are characterized by a hexagonal phase of wurtzite ZnS.

Creation of ZnS nanoparticles by laser ablation in water

We have created ZnS nanoparticles using pulsed laser ablation of ceramic target in water with an aim to produce nanoparticles with uniform distribution of the size. The particle size, structure, and physical properties were systematically investigated by X-ray diffraction (XRD), Raman spectra, high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and energy-dispersive spectroscopy. The ZnS nanoparticles were confirmed from XRD, Raman and SAED patterns to possess the sphalerite structure. Chemical composition of the ZnS nanoparticles was found to be stoichiometric. HRTEM images exhibited well-arranged lattices with the space of 0.274 nm for (200) plane and that of 0.317 nm for (111) plane. The present results demonstrate that pulsed laser ablation in water is effective and promising to create nanoparticles with controllable size in a large scale.

RESEARCH OF MORPHOLOGY AND STRUCTURE OF 3C-SIC THIN FILMS ON SILICON BY ELECTRON MICROSCOPY AND X-RAY DIFFRACTOMETRY

Silicon carbide thin epilayers were grown on Si substrates by pulsed laser ablation of ceramic target. The influence of wafer temperature on morphological and structural properties of SiC layers was investigated by scanning electron microscopy, transmission electron microscopy and X -ray diffractometry.

Thin (0 0 1) tungsten trioxide films grown by laser deposition

Highly textured thin (0 0 1) tungsten trioxide (WO 3) films have been deposited on (0 0 1) SiO 2 substrates by XeCl excimer laser ablation of ceramic targets. The influence of the oxygen pressure and substrate temperature on the composition, crystallinity and optical properties of the films has been studied. The films were grown at pressures of 1–25 Pa and substrate temperatures from room temperature up to 670 °C. The best crystallinity was obtained for the films grown at 10 Pa and 500 °C as confirmed by XRD analyses and Raman spectroscopy. Optical transmission as high as 83% has been measured in the visible and near-infrared spectral regions. The ordinary index of refraction at wavelength of 633 nm increases with the growth temperature and reaches 1.97 at the optimum growth conditions.

Laser ablation of ceramic oxides in the presence of a RF pulsed oxygen plasma

We have carried out laser ablation of ceramic targets with synchronous pulsed injection of molecular oxygen gas ionized and dissociated by a radio-frequency discharge. Time- and space-resolved optical absorption spectroscopy diagnostics reveals that the conditions occurring in conventional ceramic laser deposition experiments, i.e. with a continuous flow of molecular oxygen, can be recovered in the novel configuration. This approach allows us to reduce sample exposure to oxygen, which may be useful to prevent substrate oxidization in coated conductor fabrication.

Laser ablation of ceramic oxides in the presence of a RF pulsed oxygen plasma

We have carried out laser ablation of ceramic targets with synchronous pulsed injection of molecular oxygen gas ionized and dissociated by a radio-frequency discharge. Time- and space-resolved optical absorption spectroscopy diagnostics reveals that the conditions occurring in conventional ceramic laser deposition experiments, i.e. with a continuous flow of molecular oxygen, can be recovered in the novel configuration. This approach allows us to reduce sample exposure to oxygen, which may be useful to prevent substrate oxidization in coated conductor fabrication.

Pb1−xCaxTiO3 thin films prepared by laser ablation of ceramic targets

Pb1−xCaxTiO3 thin films with thickness in the 200–1000 nm range have been prepared by pulsed laser deposition on Pt/TiO2/SiO2/(100)Si substrates. 10% weight PbO-rich ceramic targets have been ablated with a KrF excimer laser. It has been found that the Ca concentration of the films remains close to its concentration in the target (x = 0.24). Optimized crystalline orientation is obtained using non sintered targets, on the other hand optimized tetragonality has been found in 600 nm thick films. The films show an asymmetric ferroelectric behavior.