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A secondary ion mass spectrometer with high energy, angle and mass resolution is used to study the energy and angular distributions of ions sputtered from molybdenum (110) surface under 4 keV argon beam bombardment. The sputtering at different beam orientations is also simulated by the MARLOWE computer code. The sputtering yields, in addition to the angular distribution of sputtered particles are assessed as a function of a given angle and energy.

Transmission sputtering of thin (up to 300 A) gold films bombarded by 10 to 20 keV Ar ions is simulated by using the MARLOWE computer code. The energy spectra, angle of ejection and depth of origin distributions of ejected particles are presented. The results indicate that even for a thin film the cascading of the recoils is sufficient to produce an E−2 energy spectrum and a cosine angular distribution. The evaluated transmission-sputtering yields for various film thicknesses are compared with the amount of gold retained in a silicon substrate in dynamic recoil mixing experiments.

Thin 15 nm bilayers of antimony on silicon, or a thin 10 A antimony marker layer buried in a matrix of silicon, were irradiated with 10 keV Ar+ at room temperature with fluences in the range from 5 × 1014 to 3 × 1016 ions cm-2 Sputtering of the antimony film during ion irradiation was compensated for by simultaneous controlled deposition (dynamic mixing). 2 MeV helium backscattering was used to study the resulting films and to examine the interfacial changes occuring as a result of ion beam mixing. The amount of mixing was found to be proportional to ϕ12. The mixing efficiency was found to be in reasonable agreement with previously reported data using 200–300 keV bombarding ions but it was an order of magnitude higher than that obtained using the linear cascade mixing conditions of Sigmund and Gras-Marti. The effect of film thickness on mixing was investigated by varying the antimony film thickness in the range 50–200 A and the results were compared with those obtained using a computer simulation model based on the MARLOWE code and using a Thomas-Fermi potential with a screening length suggested by Firsov. There appears to be good agreement between the simulated and the experimentally obtained data.

Thin polyimide films deposited on silicon or metal covered glass-ceramic substrates were exposed to ion bombardment at different fluences ranging from 1 × 1012 to 1.5 × 1016 cm−2. The XPS technique was used to study the polymer stoichiometry of the near surface layers (∼ 75 A) before and after the bombardment. The results show that the stoichiometric ratio of O, N and C-groups remains approximately constant with depth for unirradiated samples. A relative enrichment of C (probably in phenyl or CHx groups) occurred in the implanted samples. Scission of CN and C=O bonds was observed, the latter being complete at doses above 1014 cm−2. Desorption of O and N was also found.

Sputtering of copper, nickel and alumium polycrystalline targets by 40 keV Ar + ions is simulated by a NIARLOWE-based computer code. Angle-of-incidence dependence of sputtering yields and depth-of-origin distributions are calculated. The angular distributions and energy spectra of sputtered particles are similar to those found earlier for low-energy sputtering.

Inelastic energy-loss in a single collisionT e and related stopping cross-sectionT e based on the Firsov model are evaluated for different screening functions in the elastic interaction potentials. Various approximations ofT e andS e for keV-ions in solids are discussed.

The binary-collision approximation (BCA) based on the MARLOWE computer code is used to simulate the energy and angular distributions of atoms sputtered from a Rh(111) crystal surface exposed to ion bombardment. The influence of the depth-of-origin and replacement collisions on these distributions is discussed. The results are compared to the molecular-dynamic (MD) simulations and the experimental data of Winograd et al , based on energy- and angle-resolved detection of sputtered neutral atoms.

Cross-sectional high resolution transmission electron microscopy has been used to obtain direct information on the in-depth radiation damage distribution of weakly damaged GaAs by Si-ion implantation. A comparison is made between the experimental data and the calculated (using TRIM computer simulations) deposited energy by nuclear stopping for the same conditions. In particular a diffusion zone, with 200–300 A width, of high point defect concentration beyond the damage peak is detected. These point defects are interpreted as As interstitials. By direct observation, information concerning the damage- and radiation-enhanced diffusion in implanted III–V compound semiconductors is obtained.

The reflection of argon ions with an energy of 50 to 500 eV from a copper single crystal is simulated on a digital computer. Three models are used to describe the interaction of the projectiles with the crystal: 1. the ion interacts in each moment only with the nearest crystal atom, 2. the ion interacts with all atoms of some microcrystallite whose atoms are assumed to be free, 3. the ion interacts with a microcrystallite of bound lattice atoms. For the Ar+–Cu and Cu–Cu interaction we use the Born-Mayer potential. A comparison of the results on the spatial and energy distributions of the ions in the different models is made. [Russian Text Ignored].

The scattering of Ar, Ne, and He ions from the Cu {100} face has been investigated by a digital computer technique; only binary elastic collisions of ions with the lattice atoms have been considered; the angular and energy distribution at various directions of incidence are discussed. The scattering by surface atomic chains and its contribution to the general picture of ion reflection were also studied.

Lattice disordering has been studied both experimentally by RBS-channelling measurements and theoretically by a Monte Carlo calculation technique. Single-crystal (100) silicon has been phosphorus implanted with an energy of 60 keV at room temperature in a 7° off-axis direction. The implanted doses varied between 5 x 10 14 and 4 x 10 15 cm −2 . Channelling measured distribution of displaced atoms is compared with damage profiles in phosphorus implanted silicon calculated by the computer code TRIM.

Many theoretical works deal with recoil mixing of thin or thick Layers on a substrate [1,2,3,4]. These studies were carried out within the assumption of isotropic angular distribution of the moving low-energy cascade atoms. This is true if E ” Eo, where E is the initial energy of the primary ions and Eo amounts to between 10 and 100 eV [5]. In this case one can expect a maximum recoil mixing efficiency at the depth of maximum energy deposition by the primary ions, i.e. where FE (\(E,\vec{\Omega },\vec{r}\)) has its maximum [3,5]. There are also many experimental works which assess this suggestion [6,7,8].

Reflection high-energy electron diffraction (RHEED) and X-ray photoelectron spectroscopy (XPS) were used to demonstrate the effects of Zn + -ion implantation and subsequent low-power pulsed laser annealing (LPPLA) on the crystallinity and the P/In ratio near the surface of InP. The influence of ion-beam effects during depth profiling by a 1 to 5 keV Ar beam on the composition of surface layers is discussed in terms of XPS data compared to computer simulation results using a dynamic model based on TRIM. Relative enrichment in P of the topmost surface layer of virgin samples along with the P deficiency below the surface is confirmed by both XPS and computer simulation data, the effect being more pronounced for higher energies of the depth-profiling Ar + beam. Severe C and O contamination is found on the ion-implanted InP surface exposed to air. The P/In ratios at and below the surface (to about 10 nm depth) differ from that for the virgin sample. Both RHEED and XPS demonstrate the efficiency of laser pulses at a power density of 6 MW/cm 2 in recovering the structure and stoichiometry of ion-implanted crystals of InP.