A single crystalline Si1-xGex overlayer on insulator is realised by the implantation of germanium into a SIMOX (Separation by IMplantation of OXygen) substrate. Two SIMOX samples were implanted with 74Ge+ at elevated temperature (≈600°C), and subsequently annealed at different temperatures and anneal ambients. The microstructure, stoichiometry, and conductivity of the Si1-xGex over-layer were studied using transmission electron microscopy, Rutherford backscattering spectrometry/ion channelling and two-probe conductivity measurements. As a result of lattice reordering after final heat treatment, and despite high defect density observed in the XTEM microstructure, the measured conductivity of the over-layer is higher than of the starting SIMOX material. These results suggest a possibility of band-gap engineering by synthesis of Si1-xGex-on-insulator.

We describe a novel means for the production of atomically-bonded thin films of a wide range of materials. The technique is a plasma and ion beam method involving synthesis of the desired surface film by plasma deposition and the simultaneous atomic mixing of the film into the substrate by low energy ion implantation from the surrounding plasma. Vacuum-arc-produced metal plasma is used for the metallic component of the film and gases can be added to form compound films. Multiple plasma generators can be used, and films of single metals, alloys, ceramics and multilayers can be formed. By repetitively pulse biasing the substrate during plasma deposition, the growing film is subjected to energetic ion bombardment, and direct and recoil ion implantation is induced. The depositing film is thereby atomically mixed to the substrate as it is formed. The films are atomically smooth, can be anywhere from a few monolayers to microns in thickness, and the interface or mixed transition zone can be tailored. Here we outline the basic plasma physics of the method and describe a number of novel surfaces which have been formed with excellent properties.

Depth profiles of elements in the surface layers of metals and metallized dielectrics were investigated by Rutherford Backscatteríng Spectrometry (RBS) (for the depth profiling of heavy elements), resonant elastic Backscattering Spectrometry (BS) of 4He+ and 1H+ (for the light elements depth profiling), Elastic Recoil Detection (ERD) of 1H+ (for depth profiling of hydrogen atoms), SIMS and AES techniques. The technological TAMEK source operated in the regime of ion beam assisted deposition (IBAD) of the metal ions (ion implantation at average beam energy ≤ 150 KeV and simultaneous deposition of the same ions at energy 100 eV) in pulse mode. Coatings were deposited on metal and glass samples at temperature of substrates T=100° C. In this report, we discuss the investigation results of samples modified by IBAD in technical vacuum produced by oil diffusion pumping. Phases like TiO, TiC, TiN, TiH are indicated in interface coating-substrate layers. The total thickness of mutually mixed metal-glass layer was found to be 400 nm and it was equal up to 3 µm for metal-metal layers. Cu/Al thin layers on a glass subsrate may be used as mirrors for powerful lasers with large (up to 5 J/cm2) energy contribution.

Amorphous silicon-containing diamond-like carbon (Si-DLC) films were processed by Ar+ ion beam-assisted deposition (IBAD) on AISI 4130, 17-7 PH, 440-C, and 4340 alloy steel specimens, as well as Cr-preplated and TiN-precoated-Cr-preplated 4340 steel specimens. Coating thicknesses ranging from 1.8 to 4.31 µm were obtained, and increased with increasing beam current density and appeared to depend on the composition of the steel substrate. Microhardness values were slightly lower for the coating on Cr-preplated 4340 steel (1,017 KHN) and substantially higher for the coating on TiN-precoated 4340 steel (1,825 KHN). The cohesion and adhesion failure loads increased with increasing coating thickness and underlying layer hardness. The adhesion failure load of the coating on TiN-precoated-Cr-preplated 4340 steel exceeded those on other substrates. The friction coefficient of the coating surface was lower for the Cr-preplated 4340 specimen and substantially lower for the TiN-precoated-Cr-preplated substrate. Wear resistance seemed to be practically the same for coated 4340 or 17-7 PH steel substrates (3.16 × 10-6 to 8.60 × 10-6 mm3 N-1m-1).

We report the results of our microstructural investigations into the origin of in-plane uniaxial magnetic anisotropies induced in Ni and Fe thin films by low energy ion beam assisted deposition. 1000 Å films were prepared by ion beam sputtering onto amorphous silica substrates under simultaneous bombardment by 100 eV Xe+ ions under an oblique angle of incidence. The induced anisotropy is studied as a function of ion-to-adsorbate atom arrival ratio, R, from values of 0 to 0.35. The maximum anisotropy field is 150 Oe for Ni and 80 Oe for Fe, but their hard axes are oriented orthogonal to each other. Asymmetric x-ray diffraction is employed to study both in-plane and out-of-plane lattice spacings and crystallographic orientation. In agreement with previous work, we find evidence of a anisotropic in-plane strain of magnitude 0.2-0.5%. In all films, the direction perpendicular to the ion bombardment is compressed relative to parallel. The uniaxial magnetic anisotropy is correlated with this in-plane anisotropic strain using a simple magnetoelastic model.

Thermal deposition and Ga+ ion beam assisted deposition of Al using TMAA have been studied. At temperatures between 95ºC and 105ºC, where thermal deposition is negligible, the introduction of a low energy Ga+ ion beam (8 to 10 keV) produces selective deposition. Ion beam seeding followed by ion beam irradiation during TMAA flow leads to consistent selectivity at this temperature range. The lowest resistivity of selectively deposited Al film is 7 µΩ-cm, only 2.5 times the bulk Al resistivity. The selective deposition rate is about 300Å/min. Depositions at higher temperature produced very low resistivity Al films, but with a decreasing selectivity ratio. X-ray diffraction showed that deposited Al films are polycrystalline, with very small FWHM.

This paper examines the ion beam-assisted deposition (IBAD) of thin boron nitride films using cryogenically condensed precursors. Low energy (1100 eV) argon and (2000 eV) deuterated ammonia beams with currents of 600-850 nA were used to mix and initiate reactions in frozen (90 K) layers of diborane (B2H6) and ammonia (NH3) or only B2H6, respectively. The resulting film is shown to be an amorphous BN coating approximately 30 Å thick.

Atomic oxygen promotes the oxidation of thin films. The authors developed a silent discharge type atomic oxygen source for thin oxide film formation. The atomic oxygen source consists of a quartz discharge tube and two cylindrical electrodes that are attached to the outside wall of the tube. The atomic oxygen concentration is estimated to be 3%.

The atomic oxygen source was installed in an ICB (Ionized Cluster Beam) apparatus and applied to the formation of Er-Ba-Cu-0 thin films. By introducing the atomic oxygen during deposition, a film showing superconductivity at 81K was obtained when the substrate temperature was 570ºC. Also the substrate temperature to obtain a film showing superconductivity at 77K was estimated to be 50 °C lower than that for obtaining superconducting film formation in an atmosphere of 6% ozone. The atomic oxygen source was also applied to SrTiO3 thin film formation. Electrical properties of this film were examined and compared with those of films prepared in an atmosphere of 6% ozone. The dielectric constant of SrTiO3 film was improved from 60 to 180 by introducing atomic oxygen instead of 6% ozone. Therefore the atomic oxygen source was proven to be advantageous for thin oxide film formation.

We have grown doped diamondlike carbon (DLC) thin films on Ni and Si substrates by mass separated low energy ion beam deposition. The current-voltage characteristics of these films and also a P-doped DLC / B-doped DLC diode-like device were measured. Doped DLC films show a higher electrical conductivity, which we interpret by hopping conductivity due to an increased density of localized states rather than a shift of the Fermi level. We also present first results on doping modulated DLC multilayers deposited on Si substrates. The dopant concentration profiles were analyzed by Rutherford Backscattering for 63Cu dopant atoms and by neutron depth profiling for a 10B doped multilayer.

CeO2 thin films have been deposited on patterned (100) LaAlO3 substrates using ion beam assisted deposition (IBAD) with ion beam energies between 350 and 500eV. Deposition temperatures were varied between 400°C and 600°C and deposition rates from 0.2Å/s to 1.2Å/s. Both normal and off-normal incidence ion bombardment have been studied. A trend towards planarization is observed when the ion to atom ratio is adjusted to obtain the proper degree of etching. The planarization mechanism for normal incidence bombardment appears to be similar to that previously observed for bias sputtering. X-ray diffraction shows that an initial layer of evaporated epitaxial CeO2 is required for continued epitaxial development during IBAD processing. The extent of planarization via off-normal ion incidence can be related to the direction of the ion beam with respect to the patterned features. X-ray pole figure measurements show that these films possess an in-plane orientation that is directly related to the ion beam parameters.

Diamond-like carbon films were prepared by high intensity pulsed ion beam ablation of graphite targets. A 350 keV, 35 kA, 400 ns pulse width beam, consisting primarily of carbon ions and protons, was focused onto a graphite target at a fluence of 15-45 J/cm2. Films were deposited onto substrates positioned in an angular array from normal to the target to 90° off normal. Deposition rates up to 30 nm per pulse, corresponding to an instantaneous deposition rate greater than 1 mm/sec, have been observed. Electrical resistivities between 1 and 1000 ohm·cm were measured for these films. XRD scans showed that no crystalline structure developed in the films. SEM revealed that the bulk of the films contain material with feature sizes on the order of 100 nm, but micron size particles were deposited as well. Both Raman and electron energy loss spectroscopy indicated significant amounts of sp3 bonded carbon present in most of the films.

The growth of high-quality dielectric films from Electron Cyclotron Resonance (ECR) plasmas provides for low-temperature surface passivation of compound semiconductors. Silicon nitride (SiNx) films were grown at temperatures from 30°C to 250°C on GaAs substrates. The stress in the films was measured as a function of bias applied during growth (varied from 0 to 200 V), and as a function of sample annealing treatments. Composition profiles of the samples were measured using ion beam analysis. The GaAs photoluminescence (PL) signal after SiNx growth without an applied bias (ion energy = 30 eV) was twice as large as the PL signal from the cleaned GaAs substrate. The PL signal from samples biased at -50 and -100 V indicated that damage degraded the passivation quality, while atomic force microscopy of these samples showed a three fold increase in rms surface roughness relative to unbiased samples. The sample grown with a bias of-200 V showed the largest reduction in film stress but also the smallest PL signal.

Reactive ionized cluster beam (RICB) deposition has been used to form crystalline titanium dioxide films on various substrates. Epitaxial ruble films could be formed on Al (111) and sapphire (0001) and (1120) substrates at 450 ºC and 500 ºC , respectively. We also could grow highly oriented rutile films on Si and Ge wafers and Pt (111) and (100) pdycrystal films at 400 °C . The formation of rutile films at lower substrate temperature than 500 °C has not yet been reported to be realized by other techniques.

The surface microhardness has been measured in epitaxial and polycrystal TiO2 rutile films unimplanted or implanted with 150keV He ions. The microhardness of the epitaxial films is much higher and it increases with rising dose stronger than in the case of polycrystalline films. At high doses, however, the microhardness decreases rapidly in epitaxial films. The mechanical properties of the epitaxial films are superior to those of polycrystalline films.

For a deeper understanding of the creation of carbon films the hydrogen-free ion assisted evaporation (IAE) method with neon species was used. Variation of the ion parameters energy and ion to neutral arrival ratio, delivering the necessary energy for modification of the film growth, results in different microstructures investigated with EELS, HRTEM and TED as well as different microhardnesses measured by dynamical Vickers indentation. A possible film growth mechanism is proposed based on an ion etching of mainly sp2-bonded carbon surface atoms and on defect dominated structure modification below the surface depending on the ion energy

Titanium metal is sputtered by ion beams using a Kaufman-type ion source with carbondioxide as working gas. Deposition takes place on watercooled substrates of silicon and InP. The films obtained are amorphous; they adhere excellently. SEM-pictures reveal a featureless dense fracture and a smooth surface. Despite a carbon content of 9 at % the films are highly transparent in the visible and near infrared wavelength range. Refractive indices center around 2.15 at values typically found for amorphous TiO2. The electrical properties are characterized by dielectric constant of ε = 26 ± 3, leakage current densities at breakdown of jL = 3.65 . 10-3 A/cm2 and breakdown fields EB > 1 MeV/cm.

Diamondlike carbon-nitrogen films on silicon (111) wafer and tungsten carbide plates have been prepared by using dual ion beam sputtering deposition and simultaneous bombardment by N+ with energies of 100-800 eV at room temperature. These films retain their diamondlike characteristics. However, as the nitrogen content increases from 10% at to 20% at., the Auger electron spectroscopy spectra of films change obviously in fine structure and the main Cls peak of carbon atoms in the X-ray photoelectron spectroscopy spectra shifts to 285.65 eV. The maximum hardness of these films on tungsten carbide plates is about 5260 kg/mm2. The films have an amorphous structure and smooth surface. The state of nitrogen in films and its influence on the structure and properties of films are discussed.

Thin films of Ceria, Titania and Ziroonia have been prepared using Ion Assisted Deposition(IAD). The energy of ions was varied between 0 and 1 keV and current densities up to 220 μA/cm were used. It was found that the stress behaviour is dependent on ion species, i.e. Argon or Oxygen, ion energy and current density and substrate temperature apart from the material. While oeria files showed tensile stresses under the influence of argon ion bombardment at ambient temperature, they showed a sharp transition from tensile to compressive stress with increase in substrate temperature. When bombarded with oxygen ions they showed a transition from tensile to compressive stress with increase in energy. The titania films deposited with oxygen ions, on the other hand showed purely tensile stresses. Zirconia films deposited with oxygen ions, however, showed a transition from tensile to compressive stress.

Thin films of 3,4,9,10-perylenetetracarboxylic-dianhydride (PTCDA) were deposited by an ionized beam method. The molecular orientation and chemical structure of the films were studied in connection with ionization and ion acceleration conditions. At a low ionization condition, the molecules are oriented in parallel with the substrate, and the crystallinity was improved by an appropriate ion acceleration. At higher ionization conditions, on the other hand, ion acceleration resulted in a loss of crystallinity. Deposited molecules undergo chemical change in such a condition, leading to dissociation of dianhydride groups.

Alumina films synthesized by ion beam assisted deposition (EBAD) were characterized in terms of their microstructure and residual stress. Normalized energy per deposited atom, En, ranged from 0 to 130 eV/atom. The microstructure of PVD films (En=0) is a mixture of crystalline (γ-Al2O3) and amorphous phases and IBAD films are amorphous. Density and stoichiometry vary between 2.6 and 3.1 g/cm3 and 1.3 and 1.6, respectively. Neither are dependent on either ion-to-atom arrival rate ratio, R, or En. The film porosity is in the form of small (4-6 nm) voids of density 1017 - 1018 cm-3. Bombarding gas is incorporated with 80% efficiency to levels of 4-5 at. %. A tensile residual stress of 0.3 GPa exists in PVD films. A rapid transition to high compressive stresses occurs with increased En, with a saturation of -0.4 GPa occurring at high En There is a strong correlation between gas incorporation and residual film stress. However, no existing models are capable of providing a quantitative explanation of the results.

The multilayer structures of tungsten and carbon for soft x-ray mirrors were fabricated by the low energy (<100eV) direct ion beam deposition method with various depositing ion energies. The layered structures were observed by cross sectional TEM. The undulated structures were found in the layered structures of the depositing ion energy of 6OeV and lOOeV. It becomes larger as the depositing ion energy increases, and the undulation of the upper layers was larger than that of the under layers. The undulation seems to increase in each carbon layer. These results are quite different from the results of evaluation of thick monolayer films in the previous work. Then, the interfacial composite layer was evaluated by XPS. The tungsten carbide layer was found at the W/ C interface on the C layer. However, we can not find such layer at the interface on the W layer. This result can be explained by the difference of the momentum of the depositing ion.