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Interaction of neutral beams (γ-quanta, neutrons, etc.) with atomic planes and rows is considered. Reflection of beams from these atomic systems is also considered. A possibility of space redistribution of such particles within the channel and possibility of turning them by a bent crystal is shown.

The thermal stability of laser annealed (111)-oriented silicon layers ion implanted with antimony has been studied. It is experimentally shown that thermal treatment at temperatures of 600-800 K results in an increase of the sheet resistivity. The maximum value of the resistivity was obtained at 1270 K. For an implantation dose of 1.2 × 1015 ion/cm2 a region of positive annealing was detected. It is shown that modification of the structure properties (appearance of antimony precipitates, generation of dislocations and dislocation loops decorated by the impurity) begins when the temperature is as high as 800-900 K. The structure obtained after the thermal treatment was found to be strongly dependent on that of the laser annealed samples.

Anumerical method proposed by Christel and Gibbons1for ionrange and damage distribution calculations is used in the present paper for ion range distribution calculations of heavy and light ions with several energies. The algorithm of Ref. 1 is modified in some points and is extended to range redistribution by backscattered particles.

Diffusion redistribution of ion-implanted boron and phosphorus in silicon at 1000°C in nitrogen, dry-oxygen and wet steam ambients has been inverstigated both experimentally and by computer simulation. Measured diffusion profiles cannot be obtained if we solve the diffusion equation with a constant diffusivity. Supposing that the diffusivity D is a function of dopant concentration N we have obtained the dependences D(N) for considered cases of boron and phosphorus diffusion in silicon. For both impurities the diffusion in oxidizing atmosphera found to be enhanced. The enhancement is stronger for boron than for phosphorus.

The paper reviews the experimental results concerning the ion-beam modification of adsorption and catalytic properties of solid surfaces, with ion implantation as well as ion mixing and ion deposition being analyzed. The effects of ion implantation on the electrocatalytic activity of electrode materials are generalized. Various available mechanisms of ion-beam modifications of surface properties are also analysed. Ion implantation dynamic collision effects are also specific effects, which depend on the nature of implanted ions, are considered. It is concluded that in order to interpret experimental data properly it is necessary to take into account the electronic structure of modified surface and especially that of implanted dopants. The fruitfulness of this approach is demonstrated in the case of transition metal ions interaction with carbon electrodes.

The state of the structure in (111)- and (001)-orientated Si single crystals was studied by backscattering of channelled He+ ions, transmission electron diffraction and electron microscopy techniques after Ar+, Si+ and P+ ion implantation and high temperature annealing. The formation processes of an anomalously high residual disordering in recrystallised layers were shown to be based on the deformation twinning mechanism which is unique for all types of ions. Deformation twinning in implanted layers is induced by the internal stresses caused by the action of two factors. The first is due to the chemical nature of an impurity to be implanted, particularly, to a blistering effect in the case of Ar+ implantation. The spatial inhomogeneity of the amorphized layer structure is responsible for the second factor. The role of specimen crystallographic orientation as well as the role of implantation temperature in recrystallization processes of implanted layers are discussed.

By means of transmission electron microscopy it is established that the rearrangement of silicon structure under highly intensive Ar+ ion implantation proceeds through the four following well-defined stages: (i) disorder accumulation; (ii) amorphization; (iii) solid phase epitaxy; (iv) structure modifications in the crystallized layers. The features of structure modifications during these stages of implantation are different. This is suggested to be a result of variation of the dynamic balance between the accumulation of radiation damage and thermally activated annealing.

The theory of K-electron ionization probabilities by heavy relativistic particles (protons, mesons, ions) as a function of an impact parameter is treated in the virtual photon approximation. This approximation can be used to calculate the K-X-ray yield excited by channeled negative and positive particles. For negative particles there is an enhancement of the yield under channeling conditions as compared with the random yield. The present theory predicts a considerable decrease of the depth of the K-X-ray yield dip when a positive particle velocity v → c. A comparison of the theoretical results with the experiments on total ionization cross sections has been performed and the agreement is good.

Charged particle energy loss has been calculated as a function of an impact parameter in a crystal. The quantum dielectric formalism is used when calculating the energy loss in the outer valence shell. Calculations have been carried out particularly for silicon including the zonal energy structure. Energy loss on inner electrons has been calculated in the semi-classical approximation and in the classical dipole approximation. The scope of applicability of the two approximations has been determined. The hyperchanneled particle energy loss to the loss in amorphous medium ratio has been calculated. This ratio is shown to display a peak a t particle velocities close to atomic velocities. Relation between energy loss and local electron density has been studied. Comparison with experiment is presented.

The atomistic model of the liquid phase epitaxial regrowth has been suggested. The model suggestes that the multiatomic (n > 3) nuclei are formed near the regrowth front and they as a whole are attached to the growing crystal. The present model is able to account for the orientation dependency of the crystal growth and to explain the pecularities of the defect formation during the pulsed nanosecond annealing.

Plastic deformation in silicon plates irradiated by highly intensity ion beams has been studied. Analysis of temperature fields and thermal stresses permits determination of critical parameters of an ion beam initiating plastic deformation in a plate.

The problems of collimation and focusing of neutral and high-energy charged particles at single crystals and sets of single crystal multilayed structures are considered.

Structure and impurity behaviour of silicon doped by B+ ion implantation up to dose of 2 × 1015 ion/cm2 have been investigated after lamp pulse annealing. It has been demonstrated that the implanted layer structure strongly depends on the implantation dose, light energy density, as well as the crystallographic orientation. The optimal annealing result in the structure, which is equivalent to that obtained in the thermal treatment, The impurity diffusive redistribution proved to be rather weaker then in the case of thermal treatment.

The paper deals with the amorphization of metals during light ion implantation. A statistical aspect of this problem is considered.

A semiclassical model for the calculation of the heavy ion electronic stopping cross section in a wide energy range is proposed. Two mechanisms of energy loss are considered: (i) energy loss to excitation or ionization of the target electrons by the partly screened field of moving ion nucleus is calculated in the binary encounter approximation (BEA) and (ii) energy to electron exchange is calculated on the basis of the modified Firsov theory taking into account electron-electron scattering. For the determination of the average momentum transferred in a collision of two electrons the BEA is also used. The simple universal projectile velocity dependence of the average effective ion charge is applied in calculations. On the basis of the proposed model the energy loss rate of 19F, 24Mg and 32S ions in Ti, Ni, Fe, Ag solid targets as well as 32S ions in gaseous N, and Ar within the energy interval 0.01–12 MeV/nucleon is calculated. Our results on the whole are in good agreement with experiments and th...

The compound formation and structural changes produced by boron ion implantation in vanadium thin films has been studied by electron microscopy. The compound formation depends on the film thickness and ion range.

The formation and complete recrystallization of an amorphous silicon layer during highly intensive Ar ion implantation have been studied. Rutherford backscattering and electron microscopy techniques have shown some specific features of such a crystallization as compared with a conventional thermal annealing. A model of dynamic cascade annealing of secondary defects is suggested to account for the experimental results.

On emploie la microscopie electronique en transmission et la diffraction de rayons X pour etudier la structure et les modifications de composition de phases dans les couches de Ti-α sous implantation de carbone de recul. Importance d'une fine couche d'oxyde a la surface

The kinetics of structural and phase transformations in polycrystalline AL layers in the course of nitrogen implantation to the concentrations close to the equilibrium limit of nitrogen solubility, has been studied by transmission electron microscopy and electron diffraction techniques. A model is suggested according to which the nucleation of the ALN phase takes place on radiation-induced stacking faults ({111} habitus) and occurs by means of migration of nitrogen to the defect plane and the filling in the octahedral pores in the region of hexagonal packing of the layers. This process leads to a sequential formation of layers having the wurtzite structure.

Rutherford backscattering (He+, 700 keV) and transmission electron microscopy were used to investigate the character of radiation damage in Si (001) after complete regrowth of the amorphous layer. Silicon samples were implanted with 120 keV As+ ions at a dose rate ∼ 50 mA/cm2. It is shown that the formation and growth of inclusions takes place withing a depth of 35–150 nm from the surface at the fourth stage of high current density implantation. These inclusions are coherent with the single crystal matrix and have a wurtzite-type hexagonal structure with the lattice parameters a= 3.80 A and c= 6.28 A. Approximately 40 nm of the surface silicon layer retains its perfect single crystal structure after implantation. By the end of the third stage of high current density implantation silicon crystal contain very few point defects (less than 5%) within a depth between Rp and 2 Rp.

Mirror reflection of charged and neutral particles and γ-quanta on the smooth surface of solids treated. A new type of optics is also discussed.

The possible directional distributions of Burgers vectors of perfect dislocation loops and dipoles formed in the silicon single crystals after ion implantation and annealing have been studied.

The influence of the non-dipole character of radiation on the spectral characteristics of the Kumakhov radiation has been analysed. It was shown that if γψL ≦ 1, the non-dipole character can lead to an increase of the spectral intensity of radiation in its maximum. In heavy crystals the strong non-dipole character of radiation γψL > 1 leads to sharply expressed maximum in spectral distribution of the radiated energy. The influence of the non-dipole character on the temperature dependence of radiation is investigated.

On the basis of dielectric formalism the analytical expressions for the calculation of close collision and plasmon excitation contributions to the total energy loss of light ions (protons, α-particles) on valence electrons of metals have been obtained. The importance of accounting for the relation between the mentioned contributions while interpreting the results on ion dechannelling due to their multiple scattering on the crystal valence electrons has been pointed out. The ratio of the total energy loss for the best channelled light ions to the energy loss in the non- oriented target in the energy range of E ≈ 100 keV-500 MeV has been calculated.

The silicon layers structure after As+−ion implantation and subsequent pulse annealings, which were carried out in nanosecond (Q-switched ruby laser) or/and few seconds (halogen lamps) time intervals, has been studied by transmission electron microscopy techniques. It has been shawn that the structure state is determined to a large extend by pulse annealing parameters. In the case of second pulse annealing the level of ion-implanted layer disordering affects considerably the obtained structure.