Self-consistent drift-diffusion-reaction model for the electron beam interaction with dielectric samples

TL;DR

This paper develops a comprehensive self-consistent drift-diffusion-reaction model to analyze electron beam interactions with dielectric samples, capturing charging effects across multiple time scales relevant to microscopy and detector applications.

Contribution

It introduces a novel integrated modeling framework combining trapping dynamics and pulsed electron sources for dielectric charging analysis.

Findings

Model accurately predicts charging behavior over different time scales

Reveals the impact of pulsed electron beams on charge accumulation

Provides insights into steady-state and transient charging regimes

Abstract

The charging of insulating samples degrades the quality and complicates the interpretation of images in scanning electron microscopy and is important in other applications, such as particle detectors. In this paper we analyze this nontrivial phenomenon on different time scales employing the drift-diffusion-reaction approach augmented with the trapping rate equations and a realistic semi-empirical source function describing the pulsed nature of the electron beam. We consider both the fast processes following the impact of a single primary electron, the slower dynamics resulting from the continuous bombardment of a sample, and the eventual approach to the steady-state regime.