²⁵²Cf plasma desorption in ion implanted mica

Abstract

²⁵²Cf plasma-desorption mass spectrometry was first used¹ to determine the masses of heavy molecules of biological interest^2,3. In this technique ²⁵²Cf fission fragments penetrate a thin deposit of material (10⁵ cm⁻²) inducing the desorption of neutral and ionized species. The ionized species are accelerated by an external electrical field and their mass analysed using a time-of-flight (TOF) mass spectrometer run in the coincidence mode with each fission fragment. We have tried to assess the analytical and/or simulation potential of heavy-ion stimulated desorption of ions (HISD) in other fields ranging from the so-called ‘gas–grain’ interactions in astrophysics to the complex ageing of surfaces exposed to strongly ionizing environments in fast neutron fission reactors and fusion reactors. We outline here the potential of HISD for investigating ion implantation effects in insulators, and report a very strong enhancement in the HISD of ionized species from ion implanted mica. This enhancement, which generates heavy-ion clusters up to mass ∼500 AMU, grows around a critical fluence of implanted ions, and originates from two distinct types of radiation damage defects.