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The formation of supersaturated substitutional alloys by ion implantation and rapid liquid-phase-epitaxial regrowth induced by pulsed laser annealing has been studied using Rutherford backscattering, ion channeling analysis. Group-III (Ga, In) and group-V (As, Sb, Bi) dopants have been implanted into single-crystal silicon at doses ranging from 1×1015 to 1×1017/cm2. The samples were annealed with a Q-switched ruby laser (energy density ∼1.5 J/cm2, pulse duration ∼15×10−9 sec). Ion channeling analysis shows that laser annealing incorporates these dopants into substitutional lattice sites at concentrations far in excess of the equilibrium solid solubility. Channeling measurements indicate the silicon crystal is essentially defect free after laser annealing. Also values for the maximum dopant concentration (Cmaxs) that can be incorporated into substitutional lattice sites are determined for our annealing conditions. Dopant profiles determined by Rutherford backscattering are compared to model calculations which incorporate both dopant diffusion in liquid silicon and a distribution coefficient from the liquid. It is necessary to assume an interfacial distribution coefficient (k′) far greater than the equilibrium value k0 to fit the experimental data. The relationship of Cmaxs and k′ to the formation of these supersaturated alloys is discussed.

The use of X‐ray diffuse scattering to carry out detailed investigations of vacancy and interstitial loops in ion and neutron irradiated copper is discussed. The theory and interpretation of asymptotic diffuse scattering near Bragg reflections are considered, and calculations are presented for the asymptotic diffuse scattering from faulted vacancy and interstitial loops in copper. Diffuse scattering measurements near the 222 reflection for copper irradiated with fast neutrons or with high energy Ni ions are analyzed to obtain separate size distributions for vacancy and interstitial loops, and the size distributions are discussed in relation to existing electron microscopy results. Asymptotic X‐ray diffuse scattering is applied to the study of the thermal evolution of dislocation loops in Ni ion‐irradiated copper as well.

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