The trapping and distribution of charge in polarized polymethylmethacrylate under electron-beam irradiation

Abstract

A scanning electron microscope (SEM) mirror-image method (MIM) is employed to investigate the charging behaviour of polarized polymethylmethacrylate (PMMA) under electron-beam irradiation. An ellipsoid is used to model the trapped charge distribution and a fitting method is employed to calculate the total amount of the trapped charge and its distribution parameters. The experimental results reveal that the charging ability decreases with increasing applied electric field, which polarizes the PMMA sample, whereas the trapped charge distribution is elongated along the direction of the applied electric field and increases with increasing applied electric field. The charges are believed to be trapped in some localization states, of activation energy and radius estimated to be about 19.6 meV and , respectively.

Growth and decay of surface voltage on silver diffused polyimide exposed to 3–15 keV electrons

“…During a long period of exposure to radiation, negative or positive charge can be accumulated on the polyimide surface [18][19][20]. This process leads to growth of surface voltage, which can be high enough to initiate and sustain electrical 1 Author to whom any correspondence should be addressed.…”