Monte Carlo study on the temperature rise under electron irradiation

Abstract

Scanning electron microscope (SEM) is frequently-used in analysis for micro/nanoscale structural information. During SEM analysis, besides the widely-known charging effect, the temperature rise because of electron beam bombardment also has become an issue due to it can modify SEM results with the downsizing of specimen, too. In this work, a sophisticated Monte Carlo (MC) model was adopted to quantitatively study the temperature rise during SEM imaging. The influences of various parameters on temperature profile for two different systems were examined: 1) semi-infinite metal copper (Cu) bulk focused on accelerating energy, incident electron beam angle (0° to 80°), incident beam size and the number of incident electron; 2) semi-infinite insulator Silicon dioxide (SiO2) bulk (amorphous SiO2) focused on scanning duration time. It was concluded that the temperature profile presents three characteristics: a) increasing first at surface until its maximum is reached, then has a sharp reduction as a function of depth from the surface for all two systems; b) being affected seriously by accelerating energy, incident electron beam angle and scanning duration time. The mechanism behind these phenomena was explained in detail. This work provides a better understanding and elucidation for physical mechanism of electron-beam-induced deposition, of which process control, performance and reliability would thus get a greater improvement based on this study.