Ionic desorption in poly(methyl methacrylate) induced by fast electrons

摘要

Electron stimulated ion desorption (ESID) studies have been performed in poly(methyl methacrylate) (PMMA) using a time-of-flight mass spectrometer and a pulsed electron beam source with pulse duration of 0.18 mus (FWHM) and frequency of 3 kHz. The incident electron energy was 350-1200 eV. Several ionic fragments have been observed, H+ being the main ionic species desorbed. Partial ion yields have been determined for the main fragments as a function of the electron energy. They show a maximum at 500-600 eV. Ionic desorption from PMMA is tentatively discussed in terms of the Auger stimulated ion desorption (ASID) mechanism. This is, to our knowledge, the first description of ESID on polymers. (C) 2003 Elsevier Science Ltd. All rights reserved. [References: 18]