Smith D A, Fowlkes J D, Rack P D
The Department of Materials Science and Engineering, The University of Tennessee, Knoxville, Knoxville, TN 37996-2200, USA.
Nanotechnology. 2007 Jul 4;18(26):265308. doi: 10.1088/0957-4484/18/26/265308. Epub 2007 Jun 5.
A computer simulation was developed to simulate electron-beam-induced deposition (EBID). Simulated growth produced high-aspect-ratio, nanoscale pillar structures by simulating a stationary Gaussian electron beam. The simulator stores in memory the spatial and temporal coordinates of deposited atoms in addition to the type of electron, either primary (PE), back-scattered (BSE), or secondary (SE), that induced its deposition. The results provided in this paper apply to tungsten pillar growth by EBID on a tungsten substrate from WF(6) precursor, although the simulation may be applied to any substrate-precursor set. The details of the simulation are described including the Monte Carlo electron-solid interaction simulation used to generate scattered electron trajectories and SE generation, the probability of molecular dissociation of the precursor gas when an electron traverses the surface, and the gas dynamics which control the surface coverage of the WF(6) precursor on the substrate and pillar surface. In this paper, three specific studies are compared: the effects of beam energy, mass transport versus reaction-rate-limited growth, and the effects of surface diffusion on the EBID process.
开发了一种计算机模拟来模拟电子束诱导沉积（EBID）。通过模拟固定的高斯电子束，模拟生长产生了高纵横比的纳米级柱状结构。模拟器除了存储诱导沉积的电子类型（初级电子（PE）、背散射电子（BSE）或二次电子（SE））外，还在内存中存储沉积原子的空间和时间坐标。本文提供的结果适用于通过EBID在钨衬底上由WF(6)前驱体生长钨柱，尽管该模拟可应用于任何衬底-前驱体组合。描述了模拟的细节，包括用于生成散射电子轨迹和二次电子产生的蒙特卡罗电子-固体相互作用模拟、电子穿过表面时前驱体气体分子解离的概率以及控制WF(6)前驱体在衬底和柱表面的表面覆盖率的气体动力学。在本文中，比较了三项具体研究：束能量的影响、质量传输与反应速率限制生长的比较以及表面扩散对EBID过程的影响。
