Location of charge centroid in electron-beam-charged polymer films

Abstract

The centroid of the charge distribution of electron‐beam‐charged polymer films electroded on both sides is determined by measurements of the charges on, or currents into, the two electrodes during or after electron‐beam injection. Results obtained with 25‐μm Teflon FEP films charged with a diffuse monoenergetic beam of 5–40‐keV electrons show that the charge centroid is initially located between the average and maximum electron ranges regardless of whether the electrode of injection is floating or grounded (open or short circuit, respectively). During and after charging under open‐circuit conditions the centroid moves further into the material beyond the maximum range.