Xavier Stephane, Mátéfi-Tempfli Stefan, Ferain Etienne, Purcell Stephen, Enouz-Védrenne Shaïma, Gangloff Laurent, Minoux Eric, Hudanski Ludovic, Vincent Pascal, Schnell Jean-Philippe, Pribat Didier, Piraux Luc, Legagneux Pierre
Nanocarb Laboratory, Thales-Ecole Polytechnique, Route Départementale 128, 91767 Palaiseau, France.
Nanotechnology. 2008 May 28;19(21):215601. doi: 10.1088/0957-4484/19/21/215601. Epub 2008 Apr 21.
We present a fully elaborated process to grow arrays of metallic nanowires with controlled geometry and density, based on electrochemical filling of nanopores in track-etched templates. Nanowire growth is performed at room temperature, atmospheric pressure and is compatible with low cost fabrication and large surfaces. This technique offers an excellent control of the orientation, shape and nanowires density. It is applied to fabricate field emission arrays with a good control of the emission site density. We have prepared Co, Ni, Cu and Rh nanowires with a height of 3 µm, a diameter of 80 nm and a density of ∼10(7) cm(-2). The electron field emission measurements and total energy distributions show that the as-grown nanowires exhibit a complex behaviour, first with emission activation under high field, followed by unstable emission. A model taking into account the effect of an oxide layer covering the nanowire surface is developed to explain this particular field emission behaviour. Finally, we present an in situ cleaning procedure by ion bombardment that collectively removes this oxide layer, leading to a stable and reproducible emission behaviour. After treatment, the emission current density is ∼1 mA cm(-2) for a 30 V µm(-1) applied electric field.
我们提出了一种基于径迹蚀刻模板中纳米孔的电化学填充来生长具有可控几何形状和密度的金属纳米线阵列的完整工艺。纳米线生长在室温、大气压下进行，并且与低成本制造和大面积兼容。该技术能出色地控制纳米线的取向、形状和密度。它被用于制造场发射阵列，能很好地控制发射位点密度。我们制备了高度为3微米、直径为80纳米、密度约为10（7）厘米（-2）的钴、镍、铜和铑纳米线。电子场发射测量和总能量分布表明，生长出的纳米线表现出复杂的行为，首先在高场下有发射激活，随后是不稳定发射。开发了一个考虑覆盖纳米线表面的氧化层影响的模型来解释这种特殊的场发射行为。最后，我们提出了一种通过离子轰击的原位清洁程序，该程序能集体去除该氧化层，从而导致稳定且可重复的发射行为。处理后，对于施加的30伏微米（-1）电场，发射电流密度约为1毫安厘米（-2）。
