The intermetallic compound NiTi and its copper containing variants, Ni(1−x)TiCu(x), are capableof stress induced displacive tansformations which give rise to superelasticity and shape-memory effects. Thin films of these alloys, which may find use as sensors, microactuators, or as protective surface microalloys, are of increasing interest. In this study, thin films in the Ni(1−x)TiCUx) system, ranging in thickness from 250 nm to 5 μm, were prepared with a triode-type D.C. magnetron sputtering apparatus using a ternary alloy target. Both homogeneous films and periodic multilayer structures (with interspersed Ti-rich layers) were fabricated. of particular interest were shifts in composition with respect to the target, and the structural and phase transformation characteristics of the sputtered films. These phenomena were examined using transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray microanalysis. Transformation temperatures and enthalpies were determined by differential scanning calorimetry and confirmed by 4-point D.C. resistivity measurements. The as-sputtered films were amorphousbut crystallized during annealing at 923K. Electron diffraction and XPS data suggested the presence of oxygen. Single layer film compositions were shifted to slightly lower Ti fractions which depressed the onset of the transformation sequence by ˜35K and degraded phase stability during annealing. It was possible, however, to produce periodic multilayer films which showed evidence of thermoelastic phase transformations during DSC, resistivity, and in-situ TEM experiments. These films were stable with respect to vacuum annealing at 923 K for 6 h.

The effetzct of the amorphous state and the disordered sputtered state on the oxidation kinetics of nickel films was investigated by a comparison with annealed films and with pure nickel foil and powder. Specimens were exposed to oxygen in a thermogravimetric analyzer (TGA) in the temperature scan mode. An electrodeposited amorphous Ni-P alloy and sputtered pure nickel films were annealed in situ in argon and then oxidized in the same manner as the as deposited films. The as sputtered films oxidized faster at 500%C than pieces of the same film first annealed in argon. Conversely, the as deposited Ni-P film was more oxidation resistant below its crystallization temperature than the annealed Ni-P films.

An electron beam evaporation method has been used to prepare tin doped indium oxide (ITO) films with 95 wt.% In2O3 and 5 wt.% SnO2 in an oxygen atmosphere. It was found that the deposition rate and oxygen pressure strongly influence the film properties when the substrate temperature was lower than 200°C. In an optimal condition, highly transparent (transmittance ˜ 90% at wavelength 570 nm) and conductive (resistivity – 3×10−4Ω-cm) films of thickness around 2000 Å at substrate temperature as low as 180°C can be obtained.

Studies were made of the structural dependence on the growth rate and substrate temperature of Cr thin films prepared by e-beam evaporation. The d-spacings and the average size of the crystallites were determined from large angle x-ray scattering spectra. Detailed studies of the morphology were made by cross-sectional high resolution transmission electron microscopy.

The Interfacial stability of a high strength TiB2/Cu multilayer structure was examined by subjecting the layers to ion irradiation by 400 keV Ne++ ions up to a maximum dose of 12×1015 ions/cm2. Even at the highest dose, with a maximum dpa value of 4.92, the TiB2/Cu interface did not show any mixing. This stability of the multilayers has been explained by examining the maximum thermodynamic driving force for Interfacial reactions in this system.

WNx film is one of the most promising materials for self-aligned GaAs NASFET because of its low electrical resistivity and high Schottky Barrier Height at the WNx /GaAs contact.

In this paper, the effect of the sputtering conditions and the annealing environment on the chemical composition and structure of the WNx films deposited on Si and GaAs by RF reactive sputtering are studied.

The results show that with the increase of the partial pressure ratio of nitrogen gas or decrease of the working pressure, deposition rate of WNx film decreases, whereas the atomic percentage of N in the deposited film increases before approaching saturation. The WNx films formed at high working pressure (≈5 × 10−2 torr) consist of W, WN or W2N phases depending on the nitrogen partial pressure ratio. Whereas the films formed at low working pressure (≈ 3 × 10−3 torr) are usually amorphous. Annealing in a flowing N2 gas causes the crystallization of the amorphous films, which mainly consist of W+W2N. There is no change for the crystalline films. However, annealing in H2 gas causes severe loss of nitrogen of the film, the film becoming single W phase eventually.

Thin films of crystalline molybdenum oxides were formed on silicon surfaces by laser deposition. An ArF excimer laser was used to photodissociate molybdenum hexacarbonyl in an oxygen-containing ambient. Normal incidence of the laser led to the formation of very thin (< 1000 Å) films of crystalline MO4O11. The films were characterized by color, SEM, Raman spectroscopy, and X-ray diffraction.

Spectra obtained by a new soft x-ray emission spectroscopy(SXES) apparatus again exhibited clear differences among Si-compounds and Si crystal. A non-destructive analysis of an annealed transition metal(TMSi:film)/Si(111) contact system was carried out using either the distinct differences of Si L2, 3 SXES spectra between TMSi's and Si single crystals or the fad that the soft x-ray production depth increases in a solid with the energy of the primary electron, Ep. It was shown that the apparatus was capable of exploring electronic and atomic structures of a multi-layered contact system grown on a Si(111) substrate.

The thin film formation process was studied by the molecular dynamics(MD) method and by the hybrid method which combined the MD method with the Monte Carlo(MC) simulation technique. The Morse potential was assumed as the atomic interaction model. The substrate temperature was changed to see its effect on the film structure. The MD simulation found that the reconstruction process of the deposited nuclei was essential to determine the metastable film structure and that the relaxed atomic arrangements were strongly dependent on the depth of the interaction potentials. The hybrid method simulated the high rate deposition process and confirmed the results of the MD simulation.

Thin-films of Ni and Ti were formed by sputter co-deposition of Ni and Ti onto amorphous SiO2 and single crystal NaCl and Sapphire substrates. Films were characterized as follows: a) The chemical composition of the films was analysed by EDAX b) The gross morphology was examined by Scanning Electron Microscopy. c) The crystal phases were indentified by X-ray diffraction and Electron diffraction. Intermetallic NiTi has been identified in samples annealed in vacuo at 850°C. Annealing at 500°C in vacuum produced chemical separation of the Ni and Ti. This effect may be due to a narrow solidus region for the existence of NiTi and inhomogeneities due to uneven deposition of the Ni and Ti.

A series of transition metal substituted germacyclopent-3-ene compounds containing transition metal-germanium bonds have been prepared with supporting ligands which are designed to be easily removed either thermally or photochemically. In solution, model thermal decomposition experiments show that either the geramanium or the transition metal substituents may be removed, depending on the nature of the metal. Preliminary hot-wall CVD experiments using manganese and cobalt derivatives result in films with small grain size.

A series of new, molecular copper(I) compounds with the general formula (β-diketonate)Cu(PMe3) have been prepared which are specifically designed as precursors for the CVD of copper. These species have been designed such that the effects of systematic ligand variations on the CVD process can be examined. The series of derivatives where β-diketonate is one of hexafluoroacetylacetonate, 3, trifluoroacetylacetonate, 4, or acetylacetonate, 5, have been prepared in high yield and are described here. A solid state X-ray diffraction study of 3 reveals that it is monomeric. Cryoscopic molecular weight determination and gas phase FTIR spectroscopy are also consistent with a monomeric structure in liquid and gas phases. Hot-wall CVD of copper from these precursors has been examined under various conditions. Auger electron spectroscopy indicates that the films all exhibit some degree of carbon contamination, but little contamination by oxygen, fluorine or phosphorus.

By using differing target materials and admitting reactive atmospheres, thin protective coatings having an amorphous and/or metastable character such as sialon, (Ti, Al)N and (Ti, Zr)N are deposited. Phase formation, crystalline structure, morphology and mechanical properties of these films are investigated by X-ray analysis, transmisison electron microscope (TEM), scanning electron microscope, Auger electron spectroscopy (AES) and metallographic measurements. The thermal stability of the coating systems are examined and corrosion and wear test carried out.

This paper addresses an approach of predicting the effects of deposition process parameters on the film properties. The film resistivity is shown to correlate with other properties and testing conditions in explicit group form, and so is the rate of deposition with process parameters. Through a physical property relationship the two correlations merge to permit the prediction. Justifications for the correlations derive from both experimental and theoretical work already reported. Discussions on relative sensitivities of the variables toward another will follow.

In this review, recent developments in MBE growth of artificially-layered magnetic metal structures on semiconductor substrates are considered. It is seen that the ability to seed specific orientations of such structures and to probe their structural and chemical properties with a variety of in situ probes are key advantages of MBE over more conventional deposition techniques.

The 5p3/2 to 5p1/2 shallow core level branching ratios in different photoemission geometries provide a measure of the magnetic ordering in rare earth overlayers as a result of final state effects in photoemission. This 5p level anisotropy can be used to probe magnetic ordering across the Tb Curie temperature as well as magnetic ordering induced by a ferromagnetic substrate in a paramagnetic overlayer. Results are shown for paramagnetic Tb overlayers on Ni(111). The Ginzberg-Landau theory can be used to accurately model terbium thin films for T>Tc.

We have deposited Fe on (0001) and (1122) Ru surfaces. The RHEED patterns of Fe layers on these two different surfaces show perfect 2 dimensionnal epitaxy. The symmetry of the RHEED patterns is clearly 6 fold in the case of the (0001) growth direction. The RHEED patterns in the case of Fe deposited on (1122) surface are the same as those obtained from the clean Ru surface. The structure of the Fe surface is then exactly pseudomorphous to the Ru surface in both cases. Superlattices of these new Fe atomic layers with Ru have been achieved. We have deduced from X-ray diffraction, the average interplanar spacing d and we have demonstrated the hexagonal close packed stacking sequence of the entire superlattice. Plots of d versus the average atomic composition are used to determine the value of Fe interplanar spacing as 2.075Å and 1.08Å for the (0001) and the (1122) plane respectively. We are then able to determine the average Fe atomic volume, 12.8Å3. We propose that Fe is in an expanded new metastable hexagonal phase.

Epitaxial growth of Ni (111) on Si (111) has previously been obtained at room temperature by 25-keV-Ni ion beam assisted deposition, where both ion and vapor fluxes were incident at 45° to the specimen normal. This work explores the effect of a wider range of deposition conditions on epitaxial film quality. Nominally 300-nm-thick films were deposited at room temperature on Si (111) and other substrates. The substrates were sputter cleaned by the Ni ion beam immediately prior to deposition. Ion energies of 25 to 175 keV, relative ion to vapor fluxes R from 0 to 0.1, and vapor deposition rates of 0.05 to 0.5 nm/s were examined. Bragg-Brentano symmetric x-ray diffraction evaluated film quality while Ni (220) grazing-incidence x-ray diffraction rocking curves verified film epitaxy. Film quality changed gradually over these deposition parameters, with an optimum at 25 keV and an R of about 0.01. At higher energies and R values sputtering and radiation damage destroyed the film epitaxy

We used atom beam scattering (ABS), LEED and angle-resolved photo-electron spectroscopy (ARPES) to study bilayer films of Hg on Cu(001). In the surface temperature range of 180 to 330 K, the first Hg layer forms two ordered phases, a c(2×2) (with coverage=0.5 of Cu(001)) and a high density (partially commensurate) c(4×4) (coverage=0.62 ). ARPES data show that there is little or no dispersion of the 5d band of Hg. ABS data show that this layer is not flat, with in-registry Hg atoms lying about 0.15 below the not-in-registry Hg atoms. From ABS we find that the second layer forms a completely registered c(4times;4) phase. From ARPES we obtain that the second layer has an electronic structure, particularly the 5d levels, characteristic of bulk mercury.

Preliminary results of calculations of the structure of the bilayer are given.

The progression of the epitaxy of Cu(111) on Si(111) has been studied using surface sensitive techniques and the as-grown film studied using high resolution transmission electron microscopy (HRTEM). A molecular beam epitaxy (MBE) system has been used to deposit films on 3-inch-diameter silicon substrates. Across this large area a graded thickness of 0 to 10 nm of copper was deposited and scanned using Auger electron spectroscopy (AES) and low energy electron diffraction (LEED). For films grown at 373 K, silicon alloys with the copper up to a thickness of 5.0 rim. LEED indicates an ordered R30°-√3×√3 Cu(111) surface which results from the alloying of copper and silicon. HRTEM images from the interface region show the alloy to be 2.3 nm thick, crystalline, and epitaxial to the Si(111) surface. There are indications that the interface alloy may be a metastable copper silicide. This alloy is important in the mechanism for the growth of Cu(111) on Si(111).