Electron transport in thin films of polystyrene

The transport of electrons in polystyrene has been studied by charging thin films of the polymer with a low-energy (2 keV) electron beam and observing the decay of the resulting surface potential. This potential decays logarithmically with time, indicating that the electrons are detrapped over a long period. A time-dependent demarcation energy is used to analyze the detrapping process, and from this analysis information is obtained about the energy distribution of electron traps in the polymer. Above the glass transition temperature, detrapping is enhanced by the diffusion of defects at a rate determined by the micro-Brownian motion of the polymer chains.<
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