The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A dry-developed photosensitive polyimide process has been widely studied as a top surface imaging technique for photoresist applications in microsystem technology. Photografting of photoimageable polyimides are obtained by using a silicon-based monomer having methacrylate sensitizer group, analogous to that contained into the polyamic precursor resist. For this purpose standard UV lithography exposure...
In solidified metal, microscopic gas filled cavities may be present. They can originate from either gas bubbles in the melt or gas that has separated from the metal during solidification. A method has been developed to identify and open the cavities under vacuum and to determine the gas composition quantitatively. Having localised the cavity by ultrasonic methods and by X-ray imaging the method consists...
Vacuum deposited Cd 0.5 Zn 0.5 Te thin films of different thicknesses (161-450 nm) prepared by thermal evaporation in vacuum, were found to correspond to a polycrystalline cubic crystal system and exhibited p-type semiconducting behaviour. Film optical constants were determined from transmittance and reflectance measurements at normal light incidence in the spectral...
An automated fluid mechanical flow rate meter which provides for measuring gas flow rates in vacuum over the range from 10 [minus]5 to 1 m 3 Pa/s is described. The time it takes for the measurement to be carried out is not more than 5-15 min. A meter equation was derived, and constructional and operational features of the device were evaluated...
Closed-field unbalanced magnetron sputtering (CFUBMS) is now recognised as a technique capable of producing high quality industrially relevant coatings. As a result of this, BNFL are undertaking a major project with the aim of fully characterizing a CFUBMS system. As a part of this project, characterization studies have been carried out of the properties of Al, Zr and W coatings deposited by CFUBMS...
Alkanethiol self assembled monolayers of varying chain lengths have been studied by X-ray photoelectron spectroscopy. Inelastic background of the S2p peak monotonically increases with the chain length. The binding energies and peak shapes are the same for all the samples studied indicating the chemical similarity of the monolayers. However, increased packing density is seen with hexane and octanethiol...
The results from TEM study of helium porosity in nickel samples, irradiated to a fluence of 2 [times ] 10 21 He + m [minus]2 with 12 keV helium ions, and subjected to isothermal annealings for 0.5 h at 850, 950, 1050 and 1150 K, are reported. The experimental evidence for the dependence of helium porosity evolution in the implanted...
Amorphous hydrogenated carbon (a-C:H) thin films deposited by r.f. chemical vapor deposition were investigated as a chemically resistant material for masking anisotropic etching of crystalline silicon by aqueous solution of KOH. Films with thicknesses varying from 50 to 80 nm were successfully patterned on silicon slices by the lift-off process. Then the samples were submitted to one aqueous etchant...
The dc current-voltage characteristics of thin films of the metal chalcogenide glassy semiconductor As(10%)Se(90%)Cu x with 0[les ] [times ] [les ] 1 using a coplanar gold electrode were obtained. Results showed a nearly ohmic behaviour with the resistance having an Arrhenius-type dependence on the ambient temperature. The optical band gap was in the range (1.47-1.53 eV) and arose from...
A (Ba, Sr, Ca)CO 3 suspension was prepared for coating of cylindrical inserts to be used in hollow cathodes or oxide cathodes for ion sources. After determining the stoichiometric composition and coating method of the carbonate suspension, the cathodes were investigated in terms of carbonate conversion and oxide reconversion (after cathode exposure to the atmospheric air), electron emission...
Measurements were made of the electrical conductivity and differential thermal analysis on alloyed samples of Ge and Sn with Se, prepared under vacuum, to evaluate their glass-forming tendencies. It was possible to estimate the characteristic temperatures (T g , T c and T m ) and the crystallization kinetic parameters of the glasses (crystallization mode, n, rate of crystallization,...
The deposition of a- and DLC-C films from a mixture of hydrogen and methane using electron cyclotron resonance chemical vapour deposition (ECR-CVD) plus radio-frequency (RF) bias is reported. The structural characteristics of the DLC films were studied using Raman spectroscopy. The effects were investigated of the self-generated DC bias, resulting from application of RF power, on the optical gap,...
The size and shape of silver and indium nanoparticles embedded in a plasma polymer matrix formed from benzene or styrene monomer were determined by transmission electron microscopy (TEM) in lateral direction and by cross-sectional transmission electron microscopy (XTEM) in vertical direction. In multilayer assemblies consisting of plasma polymer/plasma polymer metal composite/plasma polymer [ABA],...
To investigate processes occurring during thin-film deposition by plasma chemical vapor deposition, a study was made of the radical species in an RF CH 4 /H 2 plasma using photoionization mass spectrometry. The method avoids fragmentation of particles as can occur in conventional mass spectrometry by using photons for their ionization. In the present experiment, a capacitive 13.56-MHz...
The performance of a steered-arc evaporation source is compared to the unbalanced magnetron, as to its performance in the preparation of elemental and reactively produced compound films. Materialsinvestigated include Al, Ti, Cu, TiN, and Al 2 O 3 . In reactive processing the ionised metal constituent provided by arc evaporation appears to make the kinetics of the substrate reaction...
Ratios of M 2,3 W Auger peak heights of gold and copper for the A u 0.6 Cu 0.4 alloy expected for particular compositions of two surface atomic layers and for two incidence angles of the primary electron beam in an RFA spectrometer were calculated with the use of Monte-Carlo computer simulation of the process of Auger electron transport to the...
In a search for the mechanism of the induced reduction reaction that occurred in X-ray photoelectron Spectroscopy (XPS) depth profiles measured experimentally on CeO 2 /Si epilayers grown by ion beam epitaxy (IBE), several possibilities have been checked. The first possibility, that the X-ray induces the reaction has been ruled out by experimentation. Other possible models for the incident-ion...
The properties of titanium nitride and the effects of a post-treatment by ion implantation on coatings made of it are first considered in terms of data available from the scientific literature; 70 references are cited. Data obtained in the present work are then combined with these to offer an explanation of the process mechanisms and structural effects involved. The present work covers monolithic...
Energy distributions of N + and N 2+ ions bombarding the aluminium cathode of a glow discharge at high current densities (few mA cm -2 have been calculated and compared with experimentally determined values. The results show a high proportion of N + compared to (N 1+ + N 2+ ) which are characteristic of a nitrogen discharge and arise...
Quantitative XPS analysis was used to examine the modification in a thin silica surface of its stoichiometry by the determination of nO/nSi atomic ratios after Ar + -ion and He + -ion bombardment under the fixed conditions of 1 keV energy and 1.5 10 16 ions cm -2 fluence for Ar + -ions; and 3 keV and 1 10 17 ions cm -2 ...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.