We investigate a laterally extended dielectric helium discharge system with plane electrodes. The system is operated in the glow mode and is known to exhibit a rich variety of self-organized lateral patterns in the current distribution, most of them being filamentary. It is known from theory that surface charges on the dielectrics play a major role for the emerging patterns. In this work we present a method to measure the spatial charge distribution on the dielectrics via the Pockels effect of a bismuth-silicon-oxide crystal. The experimental results of the surface-charge distribution measurements are in good agreement with previous numerical solutions of the corresponding transport equations.

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Dopant profiles created by MeV proton implantation in float zone and Czochralski silicon are examined with spreading resistance probe measurements after annealing in the temperature range of 300-500 °C. For the description of the profile shape, two species are used, one being the implanted and mobile hydrogen and the other being an immobile irradiation induced point defect complex. The diffusion of the implanted hydrogen through the radiation damaged layer is found to be of great relevance for the resulting depth distribution of the hydrogen related donors. An effective diffusion coefficient is given for implantation into float zone silicon. Furthermore, the profile shape varies significantly with the annealing temperature. It is proposed that two donor species are generated which each exhibit a different thermal stability, and that these two species have individual depth distributions. Profiles created in Czochralski silicon seem to be additionally affected by an enhan ced generation of oxygen thermal donor species

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The impact of the thermal budget on the introduction and dissociation of hydrogen-related donor profiles in high purity silicon implanted with protons in the energy range of MeV is investigated. The hydrogen-related donors are radiation-induced defect complexes decorated by the implanted hydrogen. The appearance of the donor profiles is limited to the annealing temperature regime between about 350 °C and 500 °C. The activation of the doping profiles is limited by the diffusion of the implanted hydrogen from the end-of-range region throughout the radiation-induced damage profile. This formation process is adequately described by a diffusion model with an effective activation energy of 1.2 eV. The thermal stability of the hydrogen-related donor profiles is limited by the dissociation of the donors. The deactivation of the doping is modeled by two hydrogen-related donor species with effective dissociation energies of 2.6 eV and 3 eV. The formation and dissociation mechanisms described in the present study define the upper and lower limits of the post-implantation thermal budget, respectively, for a sensible use of proton implantation doping in crystalline silicon.