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Development of Magnetic Hollow Cold Cathode for Ion Source  [PDF]
Djamel Boubetra,M. Bouafia
Journal of Applied Sciences , 2008,
Abstract: The research presented in this study focuses on the development of ion source with hollow cold cathodes which supplies low-power and high ion-current density applications. The theoretical and experimental results were used to design a second-generation laboratory model, low-current hollow cathode. Present experiment is to design a hollow cold cathode with two application possibilities.
Study of the parameters affecting ion beam emerging from cold conical cathode ion source
El- Khabeary, H.;
Brazilian Journal of Physics , 2010, DOI: 10.1590/S0103-97332010000300013
Abstract: the aim of this work is study of the parameters affecting ion beam emerging from cold conical cathode ion source. the input discharge and output ion beam characteristics have been measured at different pressures using nitrogen and argon gases. the optimum distance between the ion exit aperture of the cathode and the movable copper ion collector plate has been determined using nitrogen and argon gases. the ion collector plate has been placed at different distances from the ion exit aperture of the cathode equal to 2, 3, 4, 4.5, 5, 5.5 and 6 cm respectively. it is found that the optimum distance between the ion exit aperture of the cathode and the ion collector plate equals 5 cm for high output ion beam current. at this optimum distance, the efficiency of the ion source reaches 28.3% and 21.3% using nitrogen and argon gases respectively. the divergence angle of the ion beam exit from the cathode aperture has been determined for each distance by measuring the ion beam diameter which obtained on the ion collector plate. it is found that at the optimum distance between the ion exit aperture of the cathode and the ion collector plate, a minimum divergence angle of the ion beam emerging from the ion source equal to 1.14o and 2.29o using nitrogen and argon gases respectively. also the aspect ratio of the ion source, the ratio between the radius of the ion exit aperture of the cathode to the distance between the ion exit aperture of the cathode and ion collector plate, has been determined.
Diamond-Like Carbon Film Deposition Using DC Ion Source with Cold Hollow Cathode  [PDF]
E. F. Shevchenko,V. A. Tarala,M. Yu. Shevchenko,A. A. Titarenko
Advances in Materials Science and Engineering , 2014, DOI: 10.1155/2014/979450
Abstract: Carbon diamond-like thin films on a silicon substrate were deposited by direct reactive ion beam method with an ion source based on Penning direct-current discharge system with cold hollow cathode. Deposition was performed under various conditions. The pressure (12–200?mPa) and the plasma-forming gas composition consisting of different organic compounds and hydrogen (C3H8, CH4, Si(CH3)2Cl2, H2), the voltage of accelerating gap in the range 0.5–5?kV, and the substrate temperature in the range 20–850°C were varied. Synthesized films were researched using nanoindentation, Raman, and FTIR spectroscopy methods. Analysis of the experimental results was made in accordance with a developed model describing processes of growth of the amorphous and crystalline carbon materials. 1. Introduction Film deposition or surface modification directly from the ion beam is one of the most promising methods because it allows controlling the energy of the particles of deposited material and has a number of advantages over the other most common methods of producing films in vacuum [1–4]. At an average energy of the ions, 1–5?keV, the deposition method of immersion ion implantation is implemented [5–7]. For obtaining ions with such energy it is convenient to use self-contained ion source based on DC glow discharge plasma allowing to regulate the ion energy and ion current density precisely and widely. Research to improve technology and equipment to carry out this process are very relevant in view of the accelerated development of micro- and nanoelectronics today. Deposition of diamond-like carbon films [8] by the above-mentioned methods using multicellular ion source (IS) “Radical-M250” [3] is known. This IS forms the ion beam with a large area of cross section. To solve the same technological challenges, we proposed [9] to use the IS based on Penning discharge with hollow cathode in crossed E × H fields. Used modification of this type of IS cannot produce ion beams of large cross-sectional area; however, it has a number of advantages over other parameters. Unlike IS “Radical-M250” in the proposed IS there is independent adjustment of the ion current density and ion energy in a wide range. Furthermore, FWHM of function of ion energy distribution in the beam of IS “Radical-M250” is 540–580?eV [3]; the same parameter at the same beam current in proposed IS can be sufficiently lower [10]. Providing a significant influence of the ion energy on properties of the synthesized films, the ion source with a narrow energy spectrum of the ions will more effectively and predictably control
Study of ion beam sputtering using a glow discharge ion source
Abdelrahman, M.M.;
Brazilian Journal of Physics , 2010, DOI: 10.1590/S0103-97332010000100005
Abstract: in this work, sputtering yield in a glow discharge ion source system has been determined using the operating parameters of the ion source. the sputtering yield is found to be varied between 0.4 to 1 atoms removed per incident ion for nitrogen while for argon between 0.2 to 1.3 atoms removed per incident ion. the feature of this ion source is high output ion beam current and small size. operation of the ion source is quite simple since a stable discharge can be obtained within a large range of main parameters such as, discharge voltage, discharge current and gas pressure. also, beam profile for argon ion beam produced from the glow discharge ion source at id = 2,3 ma (discharge current) using argon gas with different gas pressures has been investigated.
Structural and Mechanical Properties of CrNx Coatings Deposited by Medium-Frequency Magnetron Sputtering with and without Ion Source Assistance
Can Xin Tian,Bing Yang,Jun He,Hong Jun Wang,De Jun Fu
Journal of Nanomaterials , 2011, DOI: 10.1155/2011/534647
Abstract: CrNx coatings were deposited on Si (100) and WC-Co substrates by a home-made medium-frequency magnetron sputtering system with and without thermal filament ion source assistance. The structure and composition of the coatings were characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy, and transmission electron microscopy. The mechanical and tribological properties were assessed by microhardness and pin-on-disc testing. The ion source-assisted system showed a deposition rate of 3.88 m/h, much higher than the value 2.2 m/h without ion source assistance. The CrNx coatings prepared with ion source assistance exhibited an increase in microhardness (up to 16.3 GPa) and adecrease in friction coefficient (down to 0.48) at the optimized cathode source-to-substrate distance.
A new atmospheric RF cold plasma source with microhollow cathode structure
一种新型微空阴极结构的大气压射频冷等离子体源

Qiu Liang,Meng Yue-Dong,Ren Zhao-Xing,Zhong Shao-Feng,
裘 亮
,孟月东,任兆杏,钟少锋

物理学报 , 2006,
Abstract: The configuration and mechanism of a microhollow cathode discharge (MHCD) is introduced in this paper. The focus is a new type of cold atmospheric large-area plasma source, the fused hollow cathode (FHC) plasma source based on radio frequency hollow cathodes. Through its applications and related research, we present the characteristics of the hollow cathode discharge and the factors on which its characteristics depend, such as the cathode material, gas specy, frequency, gas flow, pressure, inner diameter of cathode, and the like. Two other types of related MHCD systems are given in addition.
Nanotubes as Cold Cathode Elements
Jan Janik,Peter Vinduska,Marian Marton
Advances in Electrical and Electronic Engineering , 2005,
Abstract: Several materials have been developed, investigated and have exhibited various emission properties following the intent to use them as cold cathodes. The most significant steps in the development of such materials were probably diamon/DLC thin films and nanotubes. these steps are indicating the chnology in the process of reparation and investigation of properties of various materials at the Department of Microelectronics, SUT in Bratislava [1], [2], [3], [4], [5], [8]. Recent experiments exhibit emission currents approximately 1, 195 mA/cm^2 at 6, 205 V/um for nanotubes grown on copper plate.
Ion-Induced Surface Diffusion in Ion Sputtering  [PDF]
Maxim A. Makeev,Albert-Laszlo Barabasi
Physics , 1997, DOI: 10.1063/1.120140
Abstract: Ion bombardment is known to enhance surface diffusion and affect the surface morphology. To quantify this phenomenon we calculate the ion-induced diffusion constant and its dependence on the ion energy, flux and angle of incidence. We find that ion bombardment can both enhance and suppress diffusion and that the sign of the diffusion constant depends on the experimental parameters. The effect of ion-induced diffusion on ripple formation and roughening of ion-sputtered surfaces is discussed and summarized in a morphological phase diagram.
A High Capacity Li-Ion Cathode: The Fe(III/VI) Super-Iron Cathode  [PDF]
Stuart Licht
Energies , 2010, DOI: 10.3390/en3050960
Abstract: A super-iron Li-ion cathode with a 3-fold higher reversible capacity (a storage capacity of 485 mAh/g) is presented. One of the principle constraints to vehicle electrification is that the Li-ion cathode battery chemistry is massive, and expensive. Demonstrated is a 3 electron storage lithium cathodic chemistry, and a reversible Li super-iron battery, which has a significantly higher capacity than contemporary Li-ion batteries. The super-iron Li-ion cathode consists of the hexavalent iron (Fe(VI)) salt, Na 2FeO 4, and is formed from inexpensive and clean materials. The charge storage mechanism is fundamentally different from those of traditional lithium ion intercalation cathodes. Instead, charge storage is based on multi-electron faradaic reduction, which considerably enhances the intrinsic charge storage capacity.
Statistical simulation of pattern formation on plane target surfaces by ion beam sputtering  [PDF]
Nikolay A. Kudryashov,Mikhail V. Skachkov
Physics , 2014,
Abstract: Numerical simulation of pattern formation on plane target surfaces undergoing ion-beam sputtering is carried out. Base of the mathematical model of target ion-sputtering is nonlinear evolutionary equation in which the erosion velocity dependence on ion flux is evaluated by means of a Monte Carlo method. This approach needs much computational resources, but allows to investigate the influence of ion flux parameters on surface topography. Deviation of the findings from the pattern formation predicted by the continuum model is discussed.
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