Channeled ion implantation of as+ in silicon at 300°c

Abstract

Spatial distribution and lattice location of implanted As atoms in <111> and <100> Si as well as spatial distribution of radiation defects were studied by the RBS techniques after channeled implantation of 30 keV As+ ions with a dose of 3 × 1015 cnr2 at 300°C. The profile of As atoms was observed to have two maxima due to superposition of the profiles of initially nonchanneled and dechanneled ions. The aligned As+ ion beam generates fewer defects than the random one. The radiation defect profiles both after channeled and random implantations at 300°C are of the well pronounced bimodal type with a minimum at the depth of the maximum of elastic energy losses of nonchanneled As+ ions. A model of the layer of disordered zones with vacancy-defect nuclei and interstitial-defect shells is proposed. Annealing by a ruby laser with a pulse energy density of 1 J/ cm2 and duration 40 ns results in removal of the radiation defects and flattening of the substitutional As atom profile.