i-CxSiyOzHw Films Formed by Ion Beam Assisted Deposition

1992 ◽  
Vol 279 ◽  
Author(s):  
C. G. Fountzoulas ◽  
J. D. Demaree ◽  
W. E. Kosik ◽  
W. Franzen ◽  
W. Croft ◽  
...  
Keyword(s):  
Ion Beam ◽  
Chemical Properties ◽  
Arrival Rate ◽  
Chemical Compositions ◽  
Tunneling Microscopy ◽  
Photon Tunneling ◽  
Ion Beam Assisted Deposition ◽  
Knoop Microhardness ◽  
Steel Substrates ◽  
Adhesion Friction

ABSTRACTi-CxSiyOzHw films were formed by thermal evaporation of a tetraphenyl-tetramethyl-trisiloxane diffusion pump oil onto silicon and steel substrates with simultaneous bombardment of the growing film with 40 keV Ar+ ions to decompose the (C6H5)4(CH3)4Si3O2 molecules. Both the current density of the ion beam and the oil arrival rate were varied to produce hard, adhesive films on room temperature substrates, with densities ranging from 1.4 to 2.3 g/cm3 and Knoop microhardness values (at 15 g load) from 1000 to 2100. Unlubricated friction coefficients against a 440C steel ball with a 50 g load ranged from 0.03 to 0.40, depending on deposition conditions, and all films were more wear-resistant than the substrate materials. The films were examined with RBS, hydrogen forward recoil scattering, SEM, TEM, photon tunneling microscopy, electron diffraction, and ellipsometry to ascertain and correlate their chemical compositions and microstructures with their mechanical/chemical properties (microhardness, adhesion, friction and wear).

B(1−x)Nx Alloy Films Prepared by Ion Beam Assisted Deposition

1988 ◽  
Vol 128 ◽  
Author(s):  
C. A. Carosella ◽  
G. K. Hubler ◽  
D. Van Vechten ◽  
E. P. Donovan
Keyword(s):  
Refractive Index ◽  
Ion Beam ◽  
Hexagonal Phase ◽  
Arrival Rate ◽  
Sticking Coefficient ◽  
Broad Absorption ◽  
Alloy Films ◽  
Ion Beam Assisted Deposition ◽  
Knoop Microhardness ◽  
Refractive Index Data

ABSTRACTWe have produced alloy films of B(1−x)Nx (x:0 to 0.5) via ion beam assisted deposition (IBAD). Rutherford backscattering spectroscopy (RBS) measurements show that the stoichiometric films are achieved with a nitrogen to boron atom arrival rate of N/B = 2.55. The film N/B ratio for all measured compositions is fit with a model that predicts that the nitrogen sticking coefficient is 0.36. Measurements of B(1−x)Nx film thicknesses with a profilometer confirm the value of this sticking coefficient. The BN film is transparent and has an refractive index that varies between 1.90 and 1.77 in the range 400 nm to 3100 nm. The refractive index data can be fit with the Sellmeier equation. Films 500 run thick with N/B less than 0.6 appear metallic; the index decreases linearly with increasing nitrogen content. The films have two broad absorption peaks, centered at 750 cm−1 and 1370 cm−1 that correspond to BN vibrations. The characteristics of the bands suggest that the films are amorphous or a microcrystalline hexagonal phase. The Knoop microhardness of the films generally decrease with increasing N content. Stoichiometric films have a microhardness of Hk = 20 GPa, measured with a 25 gm load.

Thermal Annealing Behavior of Si-DLC Ibad Coatings

1996 ◽  
Vol 438 ◽  
Author(s):  
C. G. Fountzoulas ◽  
J. D. Demaree ◽  
L. C. Sengupta ◽  
J. K. Hirvonen
Keyword(s):  
Room Temperature ◽  
Ion Beam ◽  
Silicon Substrates ◽  
Carbon Coatings ◽  
Dlc Coatings ◽  
Annealing Behavior ◽  
Ion Beam Assisted Deposition ◽  
Disk Friction ◽  
Knoop Microhardness ◽  
Absorption Features

AbstractAmorphous, 700 nm thick, diamond-like carbon coatings containing silicon (Si-DLC), farmed by Ar+ ion beam assisted deposition (IBAD) on silicon substrates, were annealed in air at temperatures ranging from room temperature to 600°C for 30 minutes. RBS analysis showed that the composition of the films remained the same up to 200°C, but at higher temperatures the Si-DLC coatings began to oxidize at the outer surface of the coating, forming a surface layer of SiO2. After in-air annealing at 600°C the coating had been completely converted to SiO2, with no trace of carbon seen by RBS. FTIR spectra of the unannealed coatings showed a very broad mode typical of Si-DLC bonding as well as some absorption features associated with Si and SiO2. Above 200°C the transmission mode shifted to higher frequencies which may be caused by the growth of SiO2 and the decrease of the Si-DLC film thickness. The room temperature ball-on-disk friction coefficient of the coating against a 1/2′′ diameter 440 C steel ball at 1 N load ranged from 0.2 for the original coating up to 0.5 after a 100° anneal and returned to 0.2 after annealing at 200–400°C and fell to 0.12 after a 500°C exposure. The average Knoop microhardness (uncorrected for substrate effects) was 10 GPa (1,000 KHN) for coatings annealed at temperatures as high as 400°C. All coatings up to 500 °C passed the qualitative “Scotch Tape” test.

Residual Stress Control by Ion Beam Assisted Deposition

1995 ◽  
Vol 396 ◽  
Author(s):  
G. S. Was ◽  
J. W. Jones ◽  
L. Parfitt ◽  
C.E. Kalnas ◽  
M. Goldiner
Keyword(s):  
Residual Stress ◽  
Functional Dependence ◽  
Ion Beam ◽  
Arrival Rate ◽  
Gas Content ◽  
Metallic Films ◽  
Amorphous Films ◽  
Tensile Direction ◽  
Ion Beam Assisted Deposition ◽  
Wide Range

AbstractThe origin of residual stresses were studied in both crystalline metallic films and amorphous oxide films made by ion beam assisted deposition (IBAD). Monolithic films of AI2O3 were deposited during bombardment by Ne, Ar or Kr over a narrow range of energies, E, and a wide range of ion-to-atom arrival rate ratios, R and were characterized in terms of composition, thickness, density, crystallinity, microstructure and residual stress. The stress was a strong function of ion beam parameters and gas content and compares to the behavior of other amorphous compounds such as MoSix and WS12.2 With increasing normalized energy (eV/atom), residual stress in crystalline metallic films (Mo, W) increases in the tensile direction before reversing and becoming compressive at high normalized energy. The origin of the stress is most likely due to densification or interstitial generation. Residual stress in amorphous films (Al2O3, MoSix and WSi2.2) is initially tensile and monotonically decreases into the compressive region with increasing normalized energy. The amorphous films also incorporate substantially more gas than crystalline films and in the case of Al2O3 are characterized by a high density of voids. Stress due to gas pressure in existing voids explains neither the functional dependence on gas content nor the magnitude of the observed stress. A more likely explanation for the behavior of stress is gas incorporation into the matrix, where the amount of incorporated gas is controlled by trapping.

Composition and Phase Control for Molybdenum Nitride thin Films

1994 ◽  
Vol 354 ◽  
Author(s):  
Mandar S. Mudholkar ◽  
Levi T. Thompson
Keyword(s):  
Thin Films ◽  
Energy Density ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Arrival Rate ◽  
Molybdenum Nitride ◽  
Effective Energy ◽  
Film Composition ◽  
Ion Beam Assisted Deposition ◽  
Molybdenum Nitrides

AbstractMolybdenum nitrides are active and selective hydrodenitrogenation (HDN) catalysts. The catalytic properties of molybdenum nitrides were found to be dependent on the structural properties. The purpose of research described in this paper was to synthesize molybdenum nitride thin films with well defined structures and stoichiometries using ion beam assisted deposition. The films were deposited by evaporating Mo metal, and simultaneously bombarding the growing film with low energy nitrogen ions. The phase constituents of the films were determined using x-ray diffraction and the film composition was obtained by Rutherford backscattering spectrometry.The film composition and phase constituents were strong functions of the ion-to-atom arrival rate ratio, ion energy and ion angle of incidence. Differences in the film composition for different arrival rate ratios and ion angles of incidence were interpreted based on reflection and sputtering effects. Our results suggest that phase formation was governed by the effective energy density per deposited atom. Evaluation of the effective energy density per deposited atom and its physical significance in ion beam assisted deposition is discussed.

Ion beam assisted deposition of lubricant Ag(Au) films on non-planar steel substrates

2004 ◽  
Vol 180-181 ◽  
pp. 41-43 ◽  
Author(s):  
Paolo Mosaner ◽  
Marco Bonelli ◽  
Antonio Miotello
Keyword(s):  
Ion Beam ◽  
Ion Beam Assisted Deposition ◽  
Steel Substrates

Ion-Beam-Assisted Deposition and Synthesis

MRS Bulletin ◽  
1987 ◽  
Vol 12 (2) ◽  
pp. 40-51 ◽  
Author(s):  
S.M. Rossnagel ◽  
J.J. Cuomo
Keyword(s):  
Thin Film ◽  
Particle Bombardment ◽  
Energetic Particle ◽  
Ion Beam ◽  
Chemical Properties ◽  
Film Surface ◽  
Arrival Rate ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Deposition Techniques

Concurrent energetic particle bombardment during film deposition can strongly modify the structural and chemical properties of the resulting thin film. The interest in this technique, ion-assisted deposition, comes about because it can be used to produce thin films with properties not achievable by conventional deposition. Bombardment by low energy ions occurs during almost all plasma-based thin film deposition techniques. Bombardment of a growing film, particularly by accelerated ions, can also be combined with non-plasma-based deposition techniques, such as evaporation, to simulate some of the effects observed with sputtering. The bombarding particle flux is usually controllable so that the arrival rate, energy, and species can be independently varied from the depositing flux. Thus, a basic aspect of ion-beam-based deposition techniques is the “control” often absent in plasma-based techniques. In plasmas, the voltage, current, and pressure are all interdependent. The energetic bombardment at the substrate-film interface depends on the various properties of the plasma, as does the deposition rate. It is often difficult, or even impossible, to decouple these processes. With ion-beam-based deposition techniques, the ion bombardment is essentially independent of the deposition process, and both can be more easily controlled.The incident energetic particle contributes some of its energy or momentum to irreversibly change the dynamics of the film surface. The incident particle may also be incorporated into the growing film, changing the film's chemical nature. The changes induced by particle bombardment during deposition are often not characteristic of equilibrium thermodynamics because the incident particle's energy is often many times the local adsorption or binding energy.

Surface Morphology of Nb Films by Ion Beam Assisted Deposition

1996 ◽  
Vol 440 ◽  
Author(s):  
Hong Ji ◽  
Gary S. Was ◽  
J. Wayne ◽  
Neville R. Moody
Keyword(s):  
Surface Morphology ◽  
Film Thickness ◽  
Rate Ratio ◽  
Ion Beam ◽  
Arrival Rate ◽  
Mean Square ◽  
Sapphire Substrates ◽  
Ion Beam Assisted Deposition ◽  
Ion Energies ◽  
Beam Incident

AbstractNiobium films of thickness 50 nm to 1000 nm were deposited by ion beam assisted deposition (IBAD) using ion energies of 0, 500 and 1000 eV, and R ratios (ion-to-atom arrival rate ratio) of 0, 0.1, and 0.4 on (100) silicon and (0001) sapphire substrates. The films have columnar structures and the column width increases with normalized energy (En = E × R). The surface morphology depends on both the normalized energy of the ion beam, En, and the film thickness. All films have dome-like surface features that are oriented along the ion beam incident direction. The dimension of these features increases with normalized energy and film thickness. Surface roughness also increases with normalized energy and film thickness, with the root mean square (rms) roughness increasing from 1.6 nm for the PVD sample (100 nm thick) to 36.7 nm for the IBAD film (1000 eV, R = 0.4, 800 nm thick). The surface morphology of IBAD films is the result of a combination of channeling and shadowing effects.

Microstructure and Residual Stresses in Al2O3 Prepared by Ion Beam Assisted Deposition

1993 ◽  
Vol 316 ◽  
Author(s):  
M. G. Goldiner ◽  
G. S. Was ◽  
L. J. Parfitt ◽  
J. W. Jones
Keyword(s):  
Residual Stress ◽  
Ion Beam ◽  
Arrival Rate ◽  
Film Stress ◽  
Amorphous Phases ◽  
Alumina Films ◽  
Compressive Stresses ◽  
Ion Beam Assisted Deposition ◽  
Rapid Transition ◽  
Film Porosity

ABSTRACTAlumina 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.

Mechanical and Tribological Properties of Chromium-Nitrogen Films Deposited by Ion Beam Assisted Deposition

1996 ◽  
Vol 438 ◽  
Author(s):  
E. J. Tobin ◽  
F. Namavar ◽  
H. F. Karimy ◽  
C. Colerico-Stenstrom ◽  
R. J. Bricault ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Tribological Properties ◽  
Ion Beam ◽  
Fine Grained ◽  
Mechanical And Tribological Properties ◽  
Ion Beam Assisted Deposition ◽  
Uncoated Steel ◽  
Nitrogen Ion ◽  
Steel Substrates ◽  
Chromium Evaporation

AbstractMechanical and tribological properties of chromium-nitrogen films deposited by ion beam assisted deposition (IBAD) were investigated. The films were deposited reactively, i.e., via chromium evaporation with concurrent nitrogen ion beam bombardment, on stainless steel substrates at low deposition temperatures (<200°C). Two primary deposition regimes, with differing Cr/N atom-to-ion arrival ratios, were investigated: approximately 0.8–1.0 and 2.5–3.0. Rutherford Backscattering Spectroscopic analysis showed the lower arrival ratio films to be essentially stoichiometric CrN, whereas films deposited at higher arrival ratios were Cr-rich with Cr/N ratios of about 3:1. Both films were fine grained polycrystalline (typically 5–20 nanometer crystal dimension). The stoichiometric films were approximately two times harder than the Cr-rich films., based on nanohardness indentation measurements, and possessed higher residual stress levels. Both film types substantially improved the wear resistance of stainless steel disks, based on the results of ball-ondisk wear tests against ruby balls. The best performance was obtained with Cr-rich films, which exhibited a very low wear rate and lower friction than either the stoichiometric film or the uncoated steel.

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