A new method to investigate the intense pulsed ion beam ablation of silica

Abstract

Based on the energy conservation law and the Fourier law, a concise method is employed to build 2-dimensional difference heat conduction equations with appropriate boundary conditions. This method is useful in heat conduction simulation. A formula of the evaporation yield is derived to investigate the ability of every incident ion to evaporate silica through the heat effect. Then, using an argon ion beam as an example, the temperature and evaporation yield evolution of silica is simulated using the new heat conduction model and the evaporation yield formula. Under the calculated conditions of this work, when the evaporation of silica occurs, the evaporation yield increases continuously because the number of incident ions per second during one pulse decreases. At a given time, the evaporation yield decreases with the incident ion beam density because the increase of the number of evaporated silica molecules lags behind the increase of the incident ion number. The calculated results also show that the evaporation yield increases with incident ion beam diameter for a given time and ion beam density. In addition, the corresponding physical mechanism is analyzed theoretically.