Most applications of positron beams require knowledge of the implantation characteristics for an appropriate interpretation of the experimental data. In this work, the median implantation depth as a function of implantation energy, z1/2(E), of 3-18 keV positrons and their implantation profile P(z, E) in a total of 13 thin films of atactic polystyrene, poly(styrene-co-acrylonitrile), and polymethylmethacrylate spin coated onto a silicon substrate were determined from positron lifetime measurements using a pulsed, low-energy positron beam. z1/2(E) and P(z; E) were determined from the measurement of the ortho-positronium yield obtained from the intensity I3 of the long lifetime, z1/2(E) was parametrized with the commonly used power-law fit z1/2(E) = (A/ρ)En, with ρ and E in units of g cm-3 and keV, respectively, yielding
«Most applications of positron beams require knowledge of the implantation characteristics for an appropriate interpretation of the experimental data. In this work, the median implantation depth as a function of implantation energy, z1/2(E), of 3-18 keV positrons and their implantation profile P(z, E) in a total of 13 thin films of atactic polystyrene, poly(styrene-co-acrylonitrile), and polymethylmethacrylate spin coated onto a silicon substrate were determined from positron lifetime measurement...
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