Plank H, Gspan C, Dienstleder M, Kothleitner G, Hofer F
Institute for Electron Microscopy, Graz University of Technology, Graz, Austria.
Nanotechnology. 2008 Dec 3;19(48):485302. doi: 10.1088/0957-4484/19/48/485302. Epub 2008 Nov 11.
Electron beam induced deposition (EBID) is a versatile method for the controlled fabrication of conducting, semi-conducting and non-conducting structures down to the nanometer scale. In contrast to ion beam induced deposition, EBID processes are free of sputter effects, ion implantation and massive heat generation; however, they have much lower deposition rates. To push the deposition efficiency further towards its intrinsic limits, the individual influences of the process parameters have to be explored. In this work a platinum pre-cursor is used for the deposition of conducting nanorods on highly oriented pyrolytic graphite. The study shows the influence of a beam defocus during deposition on the volume growth rates. The temporal evolution of volume growth rates reveals a distinct maximum which is dependent on the defocus introduced, leading to an increase of deposited volumes by a factor 2.5 after the same deposition times. The observed maximum is explained by an increasing and saturating electron yield contributing to the final deposition process and constantly decreasing diffusion abilities of the pre-cursor molecules toward the tip of the nanorods, which is further supported by dwell time experiments.
电子束诱导沉积（EBID）是一种通用方法，可用于可控地制造尺寸达纳米级的导电、半导电和非导电结构。与离子束诱导沉积不同，EBID过程不存在溅射效应、离子注入和大量发热现象；然而，它们的沉积速率要低得多。为了进一步将沉积效率推向其固有极限，必须探究工艺参数的个体影响。在这项工作中，使用铂前驱体在高度取向的热解石墨上沉积导电纳米棒。该研究表明了沉积过程中束散焦对体积生长速率的影响。体积生长速率的时间演变显示出一个明显的最大值，该最大值取决于引入的散焦量，这导致在相同沉积时间后沉积体积增加了2.5倍。观察到的最大值可通过对最终沉积过程有贡献的电子产率不断增加并达到饱和，以及前驱体分子向纳米棒尖端的扩散能力不断下降来解释，驻留时间实验进一步支持了这一点。
