Showing papers in "Journal of Vacuum Science and Technology in 1975"
TL;DR: In this article, a substantial fraction of the defects in epitaxial thin films are formed to accommodate part of the misfit between the stress-free lattice parameters of film and substrate.
Abstract: A substantial fraction of the defects in epitaxial thin films are formed to accommodate part of the misfit between the stress−free lattice parameters of film and substrate. This paper describes some of the complete dislocations, partial dislocations, and cracks that are made for this purpose. Also described are the optimum division of misfit between dislocations and elastic strain, and the modification of this division caused by the Peierls stress and the barrier to nucleation of dislocation half−loops. The use of misfit strain to remove dislocations, the effect of misfit strain on the mode of film growth, and the evidence for dislocation sources in epitaxial layers are discussed in brief.
668 citations
TL;DR: In this article, a simple technique for the computation of the proximity effect in electron-beam lithography is presented, which gives results of the exposure intensity received at any given point in a pattern area using a reciprocity principle.
Abstract: A simple technique for the computation of the proximity effect in electron‐beam lithography is presented. The calculations give results of the exposure intensity received at any given point in a pattern area using a reciprocity principle. Good agreement between the computed results and experimental data was achieved.
459 citations
TL;DR: Thor Thornton et al. as discussed by the authors used hollow and post-type cathode sputtering apparatuses at argon pressures of 1 and 30 mTorr to evaluate OFHC copper coatings on copper, tantalum, and stainless steel substrates.
Abstract: Thick [1–10 mil (25.4–254.0 μm)] OFHC copper coatings were deposited on copper, tantalum, and stainless‐steel substrates maintained at temperatures (T) in the 50 °–950 °C range, at rates of from 200 to 18 000 A/min, using primarily hollow and also post‐type cathode sputtering apparatuses at argon pressures of 1 and 30 mTorr. Coating structures were examined by preparing metallographic cross sections. Surface topographies and fracture cross sections were examined by scanning electron microscopy. Crystallographic orientations were determined by x‐ray diffraction. No significant deposition rate influence was found on the low‐temperature structure zones reported previously [J. A. Thornton, J. Vac. Sci. Technol. 11, 666 (1974)] or on the columnar nature of coatings formed at elevated T. Truly equiaxed grain structures were generally not observed with hollow cathodes. Annealing twins were found within the grains for T≳350 °C. Evidence of extensive recrystallization and grain growth was seen for T∠900 °C. Coatin...
405 citations
TL;DR: The mean escape depths of Si 1s, Si 2p, and O 1s photoelectrons from silicon−silicon dioxide structures were determined over a wide kinetic energy range with magnesium, aluminum, and chromium x−ray sources as discussed by the authors.
Abstract: The mean escape depths of Si 1s, Si 2p, and O 1s photoelectrons from silicon−silicon dioxide structures were determined over a wide kinetic−energy range with magnesium, aluminum, and chromium x−ray sources. Variations in photoelectron line intensity were measured as a function of oxide film thickness. Film thicknesses were determined from ellipsometric data assuming an index of refraction of 1.47 for the oxide. Discrepancies in fitting intensity data to an escape−depth curve for films <20−A thick are associated with nonstoichiometry of the oxide film near the interface. The incompletely oxidized interfacial region is identified by variations in linewidth and in binding energies of the spectral lines as well as by the deviations from predicted intensity data.
237 citations
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TL;DR: In this article, the well known electron-beam positive resist, polymethyl methacrylate (PMMA), is used as the deep-uv photoresist and its optical absorption coefficient, dissolution rate, and sensitivity are given in the deepuv wavelength region.
Abstract: Using deep‐uv light ranging from 2000 to 2600 A, submicrometer patterns in photoresist with height‐to‐width aspect ratios as high as 15 can be achieved. The well known electron‐beam positive resist, polymethyl methacrylate (PMMA), is used as the deep‐uv photoresist. Its optical absorption coefficient, dissolution rate, and sensitivity are given in the deep‐uv wavelength region. Its absorption coefficient, being a factor of two lower than that of AZ 1350J, makes it suitable for deep penetration of submicrometer‐wide beams. The negligible sensitivity at wavelengths longer than 2600 A eliminates the need for an expensive filter. Both Xe–Hg arc lamps and deuterium spectral lamps have been used to expose the resist. Chrome or aluminum masks on quartz or sapphire substrates were found satisfactory. Chevron patterns of 1.6 μm width and 0.4 μm spacing and Y–I bars of 1.6 μm width and 0.2 μm gaps were printed in 3 μm of PMMA 2041, as well as Y–I bars of 0.5 μm width and 0.25 μm gaps in 1.78 μm of PMMA 2041. The ex...
158 citations
TL;DR: In this article, the bond lengths and binding locations of the p (2×2) chalcogen (O, S, Se, and Te) overlayers on Ni(001) were investigated in detail by microscopic low-energy electron diffraction (LEED) calculations.
Abstract: The bond lengths and binding locations of the p (2×2) chalcogen (O, S, Se, and Te) overlayers on Ni(001) are investigated in detail by microscopic low−energy electron diffraction (LEED) calculations. Two convergent perturbation methods are used which are as accurate as equivalent exact calculations but which minimize the use of computation core storage and time. Normal and off−normal incidences are considered and eight partial waves are used in the calculations. The results show the p (2×2) O and S bond lengths are identical to those of the c (2×2) structures determined by Demuth et al. The larger chalcogens Se and Te form slightly different bond lengths (difference less than ±0.1 A) from those determined for the c (2×2) overlayer structures.
151 citations
TL;DR: In this article, a discussion of the difficulties of measuring adhesion is presented and some of the more recent results obtained in this way are presented, in the case of metal films on polymer surfaces, there is increasing evidence of charge transfer across the interface and electrostatic bonding may make a significant contribution to measured adhesion.
Abstract: A discussion of the difficulties of measuring adhesion. Results obtained by various methods are critically considered in the light of theoretical and other estimates of the magnitude to be expected. New ideas on scratch testing are presented and some of the difficulties associated with this method are discussed. For measuring the adhesion of thin films, it still remains as one of the most successful methods and some of the more recent results obtained in this way are presented. In the case of metal films on polymer surfaces, there is increasing evidence of charge transfer across the interface and electrostatic bonding may make a significant contribution to the measured adhesion.
140 citations
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TL;DR: In this paper, a systematic investigation of the etch rates of several materials and the dependence of etch rate on beam parameters and beam angle of incidence was conducted and the results of these measurements were presented.
Abstract: In the course of developing techniques for ion−beam etching of solid bulk materials and thin deposited films, we undertook a systematic investigation of etch rates of several materials and the dependence of etch rate on beam parameters and beam angle of incidence. Results of these measurements are presented. Under certain conditions, cones formed on the surface being etched. An explanation for this instability phenomenon is given. In most practical applications of ion−beam etching, suitable masking techniques are necessary. We have developed procedures for photoresist masking for two classes of etching: (a) high−resolution, shallow−depth etching (typical dimension ∠1 μ); (b) low−resolution, very deep etching (typical dimension ∠50 μ). The methods used will be discussed, and in particular we will consider the influence of redeposition of sputtered material and the profile of the photoresist on the final−etched wall shape.
138 citations
TL;DR: In this paper, the impact of selective absorber coatings and antireflection coatings on both flat plate and concentrating type solar collectors is covered. And the results of durability life tests on a high-temperature stable, vacuum-evaporated absorber coating consisting of layers of Al 2O3−Mo−Al2O3 are reported.
Abstract: The applications and requirements for thin film coatings in solar−thermal power systems are reviewed. The substantial impact of selective absorber coatings and antireflection coatings on both flat plate and concentrating type solar collectors is covered. The results of durability life tests on a high−temperature stable, vacuum−evaporated absorber coating consisting of layers of Al2O3−Mo−Al2O3 are reported. This coating was unaffected by 500 h at 930°C. Other tests included thermal cycling, thermal shock, ultraviolet irradiation, and solar wind simulation. An electroplated solar absorber coating for low−temperature applications (<200°C) has been developed which has a solar absorption of 0.96 and an infrared emittance of 0.07 at 100°C. A chemically etched antireflection coating for glass has been investigated. Solar transmission of 0.97 is possible with this low−cost technique.
135 citations
IBM1
TL;DR: In this paper, the spatial distribution of energy deposited in a thin polymer film of polymethyl methacrylate (PMMA) by a laterally distributed electron beam is simulated with Monte Carlo calculations.
Abstract: The spatial distribution of energy deposited in a thin polymer film of polymethyl methacrylate (PMMA) by a laterally distributed electron beam is simulated with Monte Carlo calculations. The Monte Carlo simulation includes the significant contribution from electrons that are backscattered from the substrate (Si) into the film. Equienergy density contours (eV/cm3) are calculated for specific cases of beam voltage, film thickness, beam width, and beam‐edge slope. A time‐dependent solubility model is also incorporated to simulate the time evolution of the developed contours. A size effect is observed; i.e., the development time for a line depends on the line width. This intraproximity effect is ascribed to electrons backscattered from the substrate.
130 citations
TL;DR: In this article, the experimental requirements for maximizing the infrared reflection-absorption bands from a thin layer on a metal surface were discussed and the experimental performance of a particular experimental system (e.g., using only one reflection or using two reflections) relative to the theoretical best performance of the optimum system was determined.
Abstract: This paper discusses the experimental requirements for maximizing the infrared reflection–absorption bands from a thin layer on a metal surface Calculated curves are shown for 19 different metals for two spectral regions (2100 and 500 cm−1) From these curves, one can determine the performance of a particular experimental system (eg, using only one reflection or using two reflections) relative to the theoretical best performance of the optimum system In many cases, one reflection may yield a band intensity acceptably close to the maximum theoretical intensity
TL;DR: In this paper, a form of deposition in which material is vaporized in a crucible and the vapor then ejected through a fine nozzle at the focus of an electron beam in a high vacuum is described.
Abstract: We describe a form of deposition in which material is vaporized in a crucible and the vapor then ejected through a fine nozzle at the focus of an electron beam in a high vacuum. The vapor, on emerging from the nozzle, is partially condensed into clusters that are ionized by electron bombardment and then accelerated onto the substrate. The deposited films show good adhesion and large crystallite size. Examples include the deposition of Cu onto glass, Si onto Si, and ZnS onto NaCl.
TL;DR: In this paper, the authors report the generation of intense beams of metal ions of Li, Cs, Sn, Ga, and Hg by field ionization of molten metal films on solid wire needles.
Abstract: Intense ion beams are of interest in fusion research for plasma heating, diagnostics, and target compression and in industry for implantation, microfabrication, etc.We report the generation of intense beams of metal ions of Li, Cs, Sn, Ga, and Hg by field‐ion emission of molten metal films on solid wire needles. The source is extremely simple and is based on electrohydrodynamic instabilities induced in liquid films under electric stress. In practice, for a point‐source or needle emitter, a tungsten needle protrudes from the surface of the molten metal which, with good wetting, flows as a thin film to the needle apex. Application of a potential difference between the needle anode and an apertured cathode results in an electrohydrodynamic instability in the film which is manifested as a filamentary cusp at the needle apex. The electric field intensity at the cusp is sufficient to produce intense atomic‐ion emission by field ionization. When the protruding length of the needle through the molten metal pool i...
TL;DR: In this article, a system for high-speed, electron-stimulated Auger electron spectroscopy (AES) and x−ray photoelectron spectroscope with a double-pass cylindrical−mirror analyzer (CMA) is described.
Abstract: A system which accomplishes high−speed, electron−stimulated Auger electron spectroscopy (AES) and x−ray photoelectron spectroscopy with a double−pass cylindrical−mirror analyzer (CMA) is described. The CMA is well suited for AES because of its very high transmission, but has found very limited use in ESCA studies. In the present system the required source definition for use with a large−diameter x−ray beam is achieved with a two−stage CMA. The required energy resolution for ESCA is achieved with spherical retarding grids. A signal level of 16000 cps is attained on the Ag 3−d lines at 1.25−eV FWHM with a 400 W, Mg anode, x−ray source. Adequate luminosity is achieved primarily through high transmission, rather than a large imaged sample area. The small imaged area (less than 2−mm diam) is useful for selected area analysis and simplifies in−depth analysis when combined with inert−gas sputtering.
TL;DR: In this article, depth-concentration profiling has emerged as one of the most important applications, owing to the high-depth resolution obtainable, but the intrinsic depth resolution of some 10 A is degraded by uneven erosion, sample mixing owing to atomic collisions, and at very low concentration, profiling by the sample consumption required.
Abstract: During the past decade, since commercial instruments have become available, secondary−ion mass spectrometry has been increasingly applied as a very sensitive technique for surface characterization. Depth−concentration profiling has emerged as one of the most important applications, owing to the high−depth resolution obtainable. The intrinsic depth resolution of some 10 A is degraded by uneven erosion, sample mixing owing to the atomic collisions, and at very low concentration, profiling by the sample consumption required. Quantitative analyses are more difficult than with other techniques, but are feasible. The utilization of chemical signal enhancement by oxygen flooding or oxygen bombardment is very helpful.
TL;DR: In this paper, the surface composition of four Cu−Ni alloys was measured using the M1M4,5M4-5 transitions at ∠100 eV, and it was shown that the copper concentration in the surface is significantly larger than that in the bulk.
Abstract: In previous Auger studies of the Cu−Ni alloys, most workers, using Auger transitions at ∠900 eV, have found that the ’’surface composition’’ and bulk composition are the same. We have measured the surface composition of four Cu−Ni alloys using the M1M4,5M4,5 transitions at ∠100 eV. In all samples studied [polycrystalline 10%/90%, (100) 10%/90%, (110) 10%/90%, and (100) 50%/50%, Cu/Ni], the copper concentration in the surface is significantly larger than that in the bulk. The discrepancy between our results and those of the early workers is due to the different escape depth of the emitted electrons as a function of electron energy. We estimate that the 100 eV transitions are sensitive to about one to two layers, whereas the high−energy transitions are sensitive to five to eight layers. The presence of adsorbates can alter the surface composition. This effect will also be discussed.
TL;DR: In this article, a capacitance probe was used to detect the deflection occurring during ion implantation of thin specimens of annealed steel, which is related to the introduction of a surface compressive stress.
Abstract: Recent work on ion−implanted metals has demonstrated the existence of substantial changes in friction and wear properties brought about by ion implantation. The effects have been attributed to corrosion inhibition, metallurgical transformation, or mechanical surface hardening. In the work to be presented, a capacitance probe apparatus is described which has been used to detect the deflection occurring during ion implantation of thin specimens of annealed steel. The deflection is related to the introduction of a surface compressive stress. 100−keV argon ion implantation is found to produce surface stresses of several thousand lbs/in.2 which reach a maximum at a dose approximately 5.0×1016 ions−cm−2. Light ions, such as nitrogen, which form chemically stable compounds within the steel, generate similar stresses within the surface such that a macroscopic deflection of the specimen can be observed. In this case very high doses are required to maximize the stress (∠1017 ions−cm−2). The results are interpreted with reference to damage mechanisms and nitride formation, and are discussed in relation to the mechanical property changes previously reported.
TL;DR: In this article, a metal alloy target of indium doped with about 5% by weight tin was sputtered in 100% oxygen onto quartz substrates and then annealed at temperatures up to 600°C in an argon−flow system.
Abstract: A metal alloy target of indium doped with about 5% by weight tin was rf sputtered in 100% oxygen onto quartz substrates. These films of indium−tin oxide were then annealed at temperatures up to 600°C in an argon−flow system. Their optical and electrical properties were examined as a function of annealing temperature. Optimum film properties include a sheet resistance of 2−3 Ω/⧠ with a transparency of 95% over the entire visible region. Optical extinction coefficients, percent transmission, and refractive indices were determined as a function of annealing temperature and sheet resistance. Results show that the infrared reflection loss of films of indium−tin oxide can be attributed to the amount of oxygen vacancies which are incorporated into the film.
TL;DR: In this paper, an equation relating the resonant frequency of the composite system to the mass and acoustic impedance of deposited material can be derived, showing that materials with different acoustic impedances will obey different mass−frequency relations.
Abstract: Early investigations on quartz crystal resonators indicated, that for small mass change, the frequency shift is linearly proportional to the added mass. The accuracy of mass determination was later improved somewhat by using the so−called ’’period measurement’’ technique, which assumes a linear relationship between added mass and change in period of oscillation. However, recent studies indicate that for large mass load, the elastic properties of the deposited material have to be taken into consideration. Based on the theory of one−dimensional acoustic composite resonators, an equation relating the resonant frequency of the composite system to the mass and acoustic impedance of deposited material can be derived. The equation shows that materials with different acoustic impedances will obey different mass−frequency relations. The experimental data for a number of materials with different elastic properties are shown to be in excellent agreement with the theoretical predictions to a mass load as large as 50×...
TL;DR: In this article, the operating parameters for a field-ionization source have been measured and the beam signal-to-noise ratio has been found to increase with increasing current.
Abstract: Operating parameters for a field‐ionization source have been measured. Sensitivities of 5×10−5 A sr−1 Torr−1 were found at 77 K. Angular distributions are uniform near ϑ=0° and show the beam to be confined to ±20°. The beam signal‐to‐noise ratio was found to increase with increasing current. Calculations based on parameters of lenses in use indicate a resolution of 0.1 μm at ≳10−10 A is possible.
TL;DR: In this paper, the Auger spectrum was deconvolved using the inelastic backscatter data taken with an incident electron energy of 70 eV and the resulting Auger valence−band structure was very similar in shape to the calculated spectrum but slightly narrower.
Abstract: Previous work on the valence−band structure for the aluminum L2,3 VV transition has suffered from an arbitrary correction for the secondary electron background contribution. In the present paper this contribution is accurately assessed through the application of dynamic background subtraction and the resulting structure is shown to be a step−like function. This behavior is attributed to loss processes involving the escaping Auger electrons and is taken into account by deconvoluting the Auger spectrum using the inelastic backscatter data taken with an incident electron energy of 70 eV. The resulting Auger valence−band structure is very similar in shape to the calculated spectrum but slightly narrower. Additional data will be presented which indicate that this narrowing is a result of the surface sensitivity of the Auger technique.
TL;DR: In this article, a zirconium coated and built-up W(100) field cathode operating at high temperature (1400-1800 K) was investigated and the effect of residual gas on the emission characteristics and emitter life was also measured.
Abstract: Angular distribution, total energy distribution, and noise measurements have been carried out on both a zirconium coated and built‐up W(100) field cathode operating at high temperature (1400–1800 K). The effect of residual gas on the emission characteristics and emitter life was also measured. The results show that high brightness (∠1010 A cm−2 sr−1) operation with <10% noise levels and <1.5‐eV energy spread in a 0.079‐msr‐ beam solid angle can be achieved. Emitter longevity in excess of 1000 h in 10 nTorr (1.3 ‐ 10−7 Pa)gas pressure has been observed.
TL;DR: In this paper, the authors examined multicomponent sputtering in amorphous Gd−Co alloys and related ternary systems and showed that the sputtering yield of one component is much greater than the yield of the other elements in the system.
Abstract: Multicomponent sputtering is examined using as examples amorphous Gd−Co alloys and related ternary systems Gd−Co−Au and Gd−Co−Mo. Film composition was studied as a function of bias voltage, target voltage, pressure, system geometry and target composition. If the sputtering yield, e, of one constituent is much greater than the yield of the other elements in the system, it is possible to express the film composition as a simple function of the above parameters. For example, in the Gd−Co system eGd ≳ eCo and the Co/Gd ratio in the film is given by (Co/Gd)film = (Co/Gd)target/1 − K (Vb/Vt), where Vb is the effective bias voltage, Vt is the target voltage, and K is a system constant which depends largely on the geometry. The equation involves a number of simplifying assumptions which are only valid in the low bias, low pressure regime. A more complex expression must be used outside of these limits. It has also been shown that there is a simple relationship between sputtering gas incorporation in the film and the effective bias voltage, which provides an independent check on the validity of the sputtering equation.
TL;DR: In this article, an impact−ionization model was proposed to predict a negative resistance type of dielectric instability and breakdown in wide bandgap insulators, where the instability develops by the injection of electrons from the cathode, impact ionization of the lattice, and a distortion of the electric field which leads to a further increase in impact ionisation.
Abstract: An impact−ionization model predicts a negative resistance type of dielectric instability and breakdown in wide bandgap insulators. The instability develops by the injection of electrons from the cathode, impact ionization of the lattice, and a distortion of the electric field which leads to a further increase in impact ionization. For the case of thin films, it is necessary to invoke a nonlocal ionization rate in order to obtain a negative resistance instability. O’Dwyer’s avalanche theory of breakdown, which applies well to semiconductors, cannot be used to predict a negative resistance in the small multiplication limit appropriate to wide bandgap insulators. The impact−ionization model presented here depends upon two critical parameters: the ionization bandgap of the material and the electron−LO phonon scattering length. Evaluated for the exemplary case of SiO2, the model predicts a current density and an average field at breakdown which increase rapidly for film thickness below 200 A.
TL;DR: In this paper, an extensive investigation of the atomic arrangement on the (001) Au surface has been performed using the techniques of positive−ion−channeling spectroscopy (PICS), LEED, and AES.
Abstract: An extensive investigation of the atomic arrangement on the (001) Au surface has been performed using the techniques of positive−ion−channeling spectroscopy (PICS), LEED, and AES. Both the normal surface in which the Au atoms are ordered in a square array and the reordered surface where it is proposed that the topmost layer of Au atoms are ordered in a hexagonal array have been examined. LEED and AES have been used in determining that the normal atomic arrangement producing the (1×1) LEED pattern is observed only when contamination is present, while the reordered surface producing the complex (5×20) LEED pattern is observed on surfaces which are atomically clean. The yield and energy distributions of 1 MeV 4He+ ions scattered from the oriented Au crystals have been used to determine the number of effective monolayers constituting the normal and reordered surfaces. Single alignment surface peaks and minimum yields have been determined, and experimental data are compared with predictions made by computer si...
TL;DR: In this paper, the authors used the self−consistent statistical exchange (Xα) scattered wave method to yield three main peaks in the ultraviolet photoemission spectrum of CO chemisorbed on Ni (100).
Abstract: Our cluster model calculations, using the self−consistent statistical exchange (Xα) scattered wave method, yield three main peaks in the ultraviolet photoemission spectrum of CO chemisorbed on Ni (100). This is consistent with the experimental observations. However, our calculations imply rather large bonding and relaxation shifts. The molecular orbitals 5σ and 1π of CO are found to interact with the metal 3d, in addition to 4s and 4p orbitals, contrary to some previous suggestions. Furthermore, we predict a chemisorption level near the top of the Fermi level, which presumably has not been detected experimentally due to interference with the high density of Ni d−states. A possible mechanism for CO bonding which emerges from our calculations is discussed.
TL;DR: In this paper, a time-of-flight spectrometer for photoelectron spectroscopy is described, which is based on the pulsed structure of the synchrotron radiation emitted from the storage ring (SPEAR) at SLAC with a pulse width of 1.5 nsec and a repetition period of 780 nsec.
Abstract: A time−of−flight spectrometer for photoelectron spectroscopy is described. It is based on the pulsed structure of the synchrotron radiation emitted from the storage ring (SPEAR) at SLAC with a pulse width of 1.5 nsec and a repetition period of 780 nsec. The sample is irradiated with monochromatic light from a soft x−ray grazing incidence monochromator which works in the photon energy range of 25−1500 eV. The time−of−flight spectrometer consists of a 6 in. mu−metal drift tube which can be pivoted around the sample making angularly resolved photoelectron spectroscopy feasible in both the horizontal and vertical direction. On the sample side of the drift tube a retardation sector is attached and on the other side, a fast channelplate detector. The design parameters are 100 MeV energy resolution at 5 eV at 1° angular resolution. Some preliminary results on single crystals are described.
TL;DR: In this paper, the wear behavior of composite coatings consisting of TiC and Ti-carbonitrides of varying composition is considered, and it is shown how roughness and surface structure of TiN layers produced by the CVD method vary in dependence of the deposition temperature but at equal deposition rate.
Abstract: Cemented carbide parts coated with several‐micron‐thick layers of hard material are now used in large quantities in machining, particularly for turning and milling. Applications for jewelry purposes are assuming increasing importance. Following a brief survey of wear mechanisms in machining, the wear behavior of homogeneous coatings of TiC, TiN, and Al2O3 is discussed. Some conclusions concerning the wear‐reducing effect of these coatings are derived. It is found that a complex interrelationship of several factors, such as diffusion barriers, reduction of friction, thermal conductivity, and others, play an important part. Effects of hardness and chemical behavior of hard‐material coatings, especially of TiC and TiN layers on the wear decrease, are mentioned. The wear behavior of composite coatings consisting of TiC and Ti‐carbonitrides of varying composition is then considered. By incorporation of these hard materials into multiple, inhomogeneous layers, significant improvements over homogeneous single‐layer coatings are achieved. In addition to great hardness, the application of hard material layers for jewelry demands corrosion resistance, an attractive color, and good polishing characteristics. Examples for the corrosion resistance of TiC and TiN and the colors of Ti‐carbonitrides are presented. The polishing characteristics of hard‐material layers greatly depend on surface roughness. It is shown how roughness and surface structure of TiN layers produced by the CVD method vary in dependence of the deposition temperature but at equal deposition rate. Some important requirements for coatings applied to tools and jewelry articles and possible methods for their production are mentioned.
TL;DR: In this article, a fully ion-implanted miniature 8192-bit random access memory chip was fabricated using electron-beam lithography with minimum linewidth between 1 and 1.5 μm and advanced Si FET technology.
Abstract: A fully‐ion‐implanted miniature 8192‐bit random‐access memory chip has been fabricated using electron‐beam lithography with minimum linewidth between 1 and 1.5 μm and advanced Si FET technology. Device structure, processing steps, mask transfer, and reactive ion etching processes capable of fabricating device structures in the micrometer and submicrometer dimensions are described. With a minimum linewidth of 1.25 μm, the memory chip occupies an area of 1.1×1.6 mm with an array density of 5 million bits/in.2 (0.8 million bits/cm2). A typical readout access time of 90 ns was measured on a functional chip.
TL;DR: In this article, a survey of the experimental information which can be obtained for adsorbate layers on metals by photoelectron spectroscopy (valence level spectrography by UPS, quantitative analysis, and chemical shifts of adsorbates and substrate core levels by XPS), and the difficulties arising in their interpretation are discussed.
Abstract: A survey is given of the experimental information which can be obtained for adsorbate layers on metals by photoelectron spectroscopy (valence level spectroscopy by UPS, quantitative analysis, and chemical shifts of adsorbate and substrate core levels by XPS), and of the difficulties arising in their interpretation. Three levels of interpretation are distinguished: a qualitative approach using the UPS and XPS spectra as fingerprints, which works best in correlation with other methods, a semiquantitative approach which tries to extract physical insight from the measured data on an intermediate level of sophistication, and as the ultimate aim, a correlation of photoelectron spectra with the spectral density obtained from many−body theories. As examples for the first approach, results for the adsorption of CO on Ru(001) and W(110), and of oxygen on W(100) are described and discussed.