Tunable Nanosynthesis of Composite Materials by Electron-Impact Reaction
Tunable Nanosynthesis of Composite Materials by Electron-Impact Reaction
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DOI：
10.1002/anie.201004220
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发表时间：
2010-01-01
影响因子：
16.6
通讯作者：
Utke, Ivo
中科院分区：
文献类型：
--
作者：
Bernau, Laurent;Gabureac, Mihai;Utke, Ivo
在现代扫描电子显微镜中，由精细聚焦的电子束引发的纳米尺度的电子诱导反应通常被用来对辐射敏感材料的薄膜表面进行图案化。传统的聚合物和无机抗蚀剂薄膜允许定义精密掩模，用于半导体行业的进一步沉积或蚀刻工艺步骤。[1]一种新的、有前途的方法采用了新的薄膜材料，其中包括联苯自组装单分子膜、钝化的金纳米团簇、朗缪尔-布洛吉特薄膜或液体前体。将这些薄膜暴露在电子下直接产生纳米尺寸的薄膜、电线、等离子结构或导电点。[2]一个非常有希望的电子冲击纳米合成方法是取代固体或液体薄膜，并使用由注入的挥发性分子不断刷新的物理吸附的单分子层。[3]该过程可比作局部化学气相沉积；但是，分解是由于电子碰撞解离而不是热解离，从而使反应限于电子束的尺寸和活跃的电子相互作用体积。它已被证明是一个非常创新的概念，用于直接、局部、三维和微创地合成未来的光子、[4]电子、[5]和机械[6]纳米器件材料，以及用于单个碳纳米管生长[7]和原子层沉积的特定位置的催化剂图案化。[8]对于纳米级沉积，聚焦的电子束通常扫描在含有在室温下挥发的化合物的表面吸附的金属上。这种吸附的电子被主束电子(能量为kev)和发射的二次电子(能量为ev)的电子撞击解离，导致含有金属的沉积物和挥发性反应产物，后者被真空系统除去。有利的是，同样的原理允许纳米级的材料去除。为
Nanoscale electron-induced reactions being triggered by a finely focused electron beam in modern scanning electron microscopes are commonly used to pattern surfaces of thin films of irradiation sensitive material. Classical polymer and inorganic resist films allow precise masks to be defined for further deposition or etching process steps in the semiconductor industry.[1] A new, promising approach employs new film materials, among which are self-assembled monolayers of biphenyl, passivated gold nanoclusters, Langmuir–Blodgett films, or liquid precursors. The exposure of these films to electrons directly results in membranes, electrical wires, plasmonic structures, or conducting dots with nanoscale dimensions.[2]A very promising approach to electron-impact nanosynthesis is to replace the solid or liquid film and use a physisorbed monolayer that is continuously refreshed by injected volatile molecules.[3] The process can be compared to local chemical vapor deposition; however, the decomposition is due to electron-impact dissociation rather than thermal dissociation, thus keeping the reaction confined to the size of the electron beam and the active electron interaction volume. It has been proven to be a very innovative concept for direct, local, three-dimensional, and minimally invasive nanosynthesis of future photonic,[4] electronic,[5] and mechanical [6] nanodevice materials as well as for site-specific patterning of catalyst for individual carbon nanotube growth [7] and atomic layer deposition.[8] For nanoscale deposition, a focused electron beam is usually scanned over surface-adsorbed metal containing compounds that are volatile at room temperature. Electron-impact dissociation of such adsorbates by both the primary beam electrons (with keV energy) and the emitted secondary electrons (with eV energy) results in metalcontaining deposits and volatile reaction products, the latter being removed by the vacuum system. Advantageously, the same principle allows nanoscale removal of material. For