标题： 离子诱导图案形成的粘性流模型：理论与实验的一致性 显示英文标题

标题： Viscous flow model of ion-induced pattern formation: consistency between theory and experiment

摘要： 已知离子辐照可以使表面自发形成特征长度尺度仅为几个纳米的图案。图案的形成通常只发生在超过一个临界角度的情况下，这个临界角度会随着入射粒子、靶材和辐照能量的变化而变化。迄今为止，还没有完全统一的物理理论来解释这一现象。然而，由于可以从给定模型的线性稳定性分析中提取出临界角度的预测值，因此能够解释临界角度的选择性是一种简单但重要的模型有效性测试。 在本文中，我们综述了所有现有的对于硅和锗材料通过氩气、氪气和氙气在250eV到2keV能量范围内的离子辐照所形成的临界角度、波长和面内应力数据。尽管忽略了侵蚀和再分布效应（这些效应通常被认为是离子诱导图案形成的关键贡献者），我们发现粘性流动模型能够在合理物理参数范围内同时解释这三种实验数据，并且与非晶层缺陷动力学一致。这增强了粘性流动和应力驱动不稳定性作为最终统一模型的重要组成部分的可能性，该模型可以解释在离子轰击下纳米级图案的形成。 显示英文摘要

摘要： It is known that ion-irradiation can lead surfaces to spontaneously develop patterns with characteristic length scales on the order of only a few nanometers. Pattern formation typically occurs only for irradiation angles beyond a critical angle, which varies with projectile, target, and irradiation energy. To date, there is no completely unifying physical theory. However, since predictions of the critical angle can be extracted from linear stability analysis of a given model, the ability to explain critical angle selection is a simple but important test of model validity. In this paper, we survey all existing critical angle, wavelength, and in-plane stress data for noble gas broad beam ion-irradiation of silicon and germanium by argon, krypton and xenon at energies from 250eV to 2keV. While neglecting the effects of erosion and redistribution, which are widely regarded as key contributors to ion-induced pattern formation, we find that a viscous flow model is capable of explaining these three types of experimental data simultaneously using only parameters within a physically-reasonable range, and in a manner consistent with the defect kinetics of the amorphous layer. This bolsters the case for viscous flow and stress-driven instabilities as important components of an eventual, unifying model of nanoscale pattern formation under ion bombardment.