ELECTRON-PROBE MICROANALYSIS OF INSULATING MATERIALS - QUANTIFICATIONPROBLEMS AND SOME POSSIBLE SOLUTIONS

The simple fact that electrical neutrality cannot be quickly restored in insulators submitted to electron bombardment leads to a change of t he parameters of electron-specimen interaction [distortion of the phi( rho z) function] and to possible modifications of the composition of t he specimen (mobile ion migration and desorption of species). The corr elation between these macroscopic effects and their microscopic causes is the main subject of this paper. From physical arguments, the diffi culties of dealing with ab initio Monte Carlo simulations are establis hed and some strategies for reducing these spurious effects or dealing with them are deduced. In particular, an analytical model for the dis tortion of the phi(rho z) function is proposed for the first time.