ZnO is a wide-band-gap semiconductor material that is now being developed for many applications, including ultraviolet (UV) light-emitting diodes, UV photodetectors, transparent thin-film ...transistors, and gas sensors. It can be grown as boules, as thin films, or as nanostructures of many types and shapes. However, as with any useful semiconductor material, its electrical and optical properties are controlled by impurities and defects. We have reviewed the growth and analysis of carbon molecular crystals by the plasma enhanced chemical vapour deposition method. The three main synthesis methods of Carbon Nanocrystals (CNCs) are the arc discharge, the laser ablation and the chemical vapour deposition with a special regard to the later one. By two different methods ZnO layers were coated on the tubes. RF sputtering was one of the ways to directly deposit ZnO thin layer on the MWCNCs. On the other hand, we used thermally physical vapour deposition for making thin Zn film to oxidize it later. Scanning electron microscopy and also Raman spectroscopy measurements of the prepared samples confirmed the presence of ZnO nanolayers on the CNC bodies.
This paper aims to investigate the effects of fusion relevant intense pulse of energetic and high fluence deuterium ions and neutrons generated in a low energy (3.0kJ) plasma focus device (UNU/ICTP ...PFF) on stainless steel-AISI 304 samples. The irradiation was performed using different number of deuterium plasma focus shots (1, 3, 5 and 10) at a fixed axial distance of 8cm from the anode tip. X-ray diffraction spectra of irradiated samples indicated the structural phase transition from mixed ferittic-austenitic form in virgin AISI 304 SS sample to only austenitic form indicated by the presence of only γ-Fe diffraction peaks and increase in corresponding peak intensities. A small shift in all austenitic diffraction peaks towards the higher diffraction angles was observed indicating the decrease in lattice spacing by vacancy defects most probably due to energetic fusion neutrons. Field emission scanning electron microscopy and atomic force microscopy images showed the formation of nanometer sized particles on irradiated samples' surfaces. The size of nanoparticles initially decreased as the number of focus shots was increased from 1 to 3 and to 5, and later as the number of focus shots was increased to 10, the aggregations of the particles occurred to form bigger clusters. The sample surface hardness was found to decrease with increasing number of irradiation shots which can be attributed to the induction of vacancy defects by 2.45MeV fusion neutron irradiations and the increasing deposition of the copper ablated from the anode-top on the irradiated samples. The study clearly established that the plasma focus device provides intense fusion relevant pulses suitable for causing the topographical, structural and hardness changes on the surface of the irradiated SS AISI 304 which is one of the candidate materials for plasma facing components in fusion reactors.
•SS-AISI 304 irradiation by high energy deuterons and fusion neutrons in PF device•Structural transition from mixed ferritic-austenitic phase to austenitic phase•Surface topography changed to nano-sized particles and their agglomerates.•Vacancy defects might be attributed to energetic fusion neutrons irradiation.•Hardness of irradiated samples is reduced due to copper impurity deposition.
Transparent Conductive Oxide (TCO) layers due to transparency, high conductivity and hole injection capability have attracted a lot of attention. One of these layers is Indium Tin Oxide (ITO). ITO ...due to low resistance, transparency in the visible spectrum and its proper work function is widely used in the manufacture of organic light emitting diodes and solar cells. One way for improving the ITO surface is plasma treatment. In this paper, changes in surface morphology, by applying argon atmospheric pressure cold plasma, was studied through Atomic Force Microscopic (AFM) image analysis and Fourier Transform Infrared Spectroscopy (FTIR) analysis. FTIR analysis showed functional groups were not added or removed, but chemical bond angle and bonds strength on the surface were changed and also AFM images showed that surface roughness was increased. These factors lead to the production of diodes with enhanced Ohmic contact and injection mechanism which are more appropriate in industrial applications.
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