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The aim of this work is to study the effect of irradiation with heavy Xe22+ ions with energies of 165 MeV, 200 MeV, and 230 MeV on the change in the optical properties of ZrO2 ceramic. The choice of ion energies, as well as irradiation fluences of 1013-1014 ion/cm2, is primarily due to the possibility of simulating radiation damage in ceramics that occurs when overlapping damaged areas in the material, comparable to damage from fission fragments of uranium nuclei in an atomic reactor. Using UV–Vis spectroscopy methods, changes in the throughput of ceramics were evaluated depending on the irradiation fluence and the energy of incident ions. It was found that a change in the irradiation conditions leads to the formation of irradiation-induced defects with an energy of 2.4–2.45 eV in the structure, the concentration of which increases with the irradiation dose. Changes in the band gap and refractive index depending on irradiation fluence and incident ions energy indicate a change in the electronic and optical density of ceramics, as well as the formation of additional absorbing centers in the structure. © 2021 Elsevier B.V. This work was supported by the Grant No. BR09158499 ( Development of complex scientific research in the field of nuclear and radiation physics on the basis of Kazakhstan accelerator complexes) of the Ministry of Energy of the Republic of Kazakhstan.

A potentially cost-effective ion implanter for solar cells has become commercially available very recently. As the emitter dopant profiles differ from the standard diffusions, a combination of process simulation and device simulation is used to predict possible applications as front emitter. The simulations show that ion energies of 10 to 30 keV and doses in the range of 5×1014 to 7×1015cm-2 are sufficient for reducing the phosphorus peak density and, hence, obtaining cell efficiency levels above 20%, if appropriate surface passivation and wafer materials are used. The simulations strongly indicate, however, that cell efficiency improves only marginally if the cell has a fully metallized rear Al-BSF and a boron-doped Cz base in the degraded state. Simulated cells with a local rear Al-BSF show an efficiency improvement of more than 0.3% absolute in the degraded state.

Growing requirements for the optical and environmental stability, as well as the radiation resistance against high-power laser radiation, especially for optical interference coatings used in the ultraviolet spectral range, have to be met by new, optimised, thin-film deposition technologies. For applications in the UV spectral range, the number of useful oxide thin film materials is very limited due to the higher absorption at wavelengths near to the electronic bandgap of the materials. Applying ion-assisted processes offers the ability to grow dense and stable films, but in each case careful optimisation of the deposition process (evaporation rate, substrate temperature, bombarding gas, ion energy and ion current density) has to achieve a balance between densification of the layers and the absorption. High-quality coatings and multilayer interference systems with SiO/sub 2/ as the low- index material can be deposited by various physical vapour deposition technologies, including reactive e-beam evaporation, ion-assisted deposition and plasma ion-assisted deposition. In order to improve the degradation stability of dielectric mirrors for use in UV free-electron laser optical cavities, a comparative study of the properties of SiO/sub 2/, Al/sub 2/O/sub 3/ and HfO/sub 2/ single layers was performed, and was addressed to grow very dense films with minimum absorption in the spectral range from 200 to 300 nm. The films were deposited by low-loss reactive electron-beam evaporation, by ion-assisted deposition using a 'Mark II' ion source, and by plasma ion-assisted deposition using the advanced plasma source. Optical and structural properties of the samples were studied by spectral photometry, infrared spectroscopy, X-ray diffraction and reflectometry, as well as by investigation of the surface morphology. The interaction of UV radiation with photon energy values close to the bandgap was studied. For HfO/sub 2/ single layers, laser-induced damage thresholds at 248 nm were determined in the 1-on-1 and 1000-on-1 test modes as a function of the deposition technology and film thickness.

Cataloged from PDF version of article. In this study, we implanted N(+) and N(2)(+) ions into sputter deposited amorphous boron carbide (a-BC) and diamond like carbon (DLC) thin films in an effort to understand the chemical bonding involved and investigate possible phase separation routes in boron carbon nitride (BCN) films. In addition, we investigated the effect of implanted C(+) ions in sputter deposited amorphous boron nitride (a-BN) films. Implanted ion energies for all ion species were set at 40 KeV. Implanted films were then analyzed using x-ray photoelectron spectroscopy (XPS). The changes in the chemical composition and bonding chemistry due to ion-implantation were examined at different depths of the films using sequential ion-beam etching and high resolution XPS analysis cycles. A comparative analysis has been made with the results from sputter deposited BCN films suggesting that implanted nitrogen and carbon atoms behaved very similar to nitrogen and carbon atoms in sputter deposited BCN films. We found that implanted nitrogen atoms would prefer bonding to carbon atoms in the films only if there is no boron atom in the vicinity or after all available boron atoms have been saturated with nitrogen. Implanted carbon atoms also preferred to either bond with available boron atoms or, more likely bonded with other implanted carbon atoms. These results were also supported by ab-initio density functional theory calculations which indicated that carbon-carbon bonds were energetically preferable to carbon-boron and carbon-nitrogen bonds. (C) 2011 American Institute of Physics.

cited By 31; International audience; The vacuum cathodic arc deposition (CAD) process is now widely used on an industrial scale to prepare protective hard coatings on cutting tools, metal molds, etc.... It has been recognized that high ionization levels of cathodic arc discharges and high ion energy can provide advantages such as enhanced adhesion required for mechanical applications involving high loads. CAD allows deposition of a wide range of hard compounds as nitrides or carbonitrides. However, CAD is also often associated macrodroplet generation that degrades the surface roughness of coatings. The recent trend is to develop advanced nanostructured hard coatings in order to enhance properties as hardness, toughness, and oxidation resistance. This paper recalls the basic aspects of both CAD technology and nanostructured thin films synthesis. Deposition and characterization of both nanocomposite and nanolayered hard coatings are described. Mechanical behaviors of nitrides can be significantly enhanced by nanolayering. The first example deals with the development of hard nanolayered nitrides coatings for cutting tools protection. It is clearly shown in this example that TiN/AlTiN coatings perform better than CrN/AlTiN and TiN/CrN for the same periods and the best performance is reached for the thinnest periods. It is also shown, in a second example, how silicon addition in CrN can lead to enhancement of oxidation resistance associated with the nanocomposite structure. Thus, relationships are established between deposition conditions, nanostructure and mechanical behaviors or oxidation resistance of the coatings. This short review recalls that CAD remains a powerful and industrial technology for nanostructured hard coatings deposition. © 2011 Elsevier B.V.

CVD mono-crystalline diamond thin films deposited on a doped diamond and aluminum backing were employed as detectors of the radiation emitted from the laser-generated plasma. Laser-matter interactions were obtained by the use of an Nd:Yag repetitive laser at INFN-LNS in Catania operating at 1010 W/cm2 pulse intensity, and a high-power iodine PALS laser in Prague operating at 1015 W/cm2 pulse intensity. Plasmas were obtained by ablating Al, Ta, Au, and CF2 bulk targets. Plasma characterization was carried out using diamond detectors and ion collectors placed at different distances and angles in relation to the position of the ablated target. Photons, electrons, and ions hitting the sensible volume of the detector generate electronhole pairs (loosing 13 eV for a pair), resulting in an arising of the voltage signal at the device electrodes, which is proportional to the deposited energy. Diamond detectors can measure UV, X-rays, electrons, and ions. The time-of-flight (TOF) technique was exploited to separate...

The MBE growth of InGaAs layers on Si-implanted InP:Fe substrates was investigated. Ion doses and energies used were in the range of 5*1012-5*1014 cm-2 and 100-700 keV, respectively. Among the different annealing conditions tested, i.e. in-situ annealing in the MBE growth chamber at 500 degrees C, rapid thermal annealing at 650 degrees C, and high temperature annealing at 750 degrees C under PH3/H2 partial pressure, only the latter method was found to ensure restoration of the substrate crystal and high-quality overgrowth as assessed by RHEED and X-ray diffractometry. Heterojunction bipolar transistors employing an implanted overgrown collector was successfully fabricated.