STTR Phase I: Fabrication of Coaxial Nanowires/Nanocables Using Carbon Nanotubes

该小企业技术转让（STTR）第一阶段项目提供了通过原子层沉积（ALD）在碳纳米管（CNT）上沉积的复合氧化铝/钨/氧化铝（Al 2 O3/W/Al 2 O3）三层的商业化，以形成用于纳米电子应用的同轴纳米线/纳米电缆。这种同轴纳米结构可以通过首先用氧化铝（Al 2 O3）鞘的保形且无针孔的绝缘纳米层涂覆CNT来制造，以将纳米管与其周围环境隔离和绝缘。第二，导电W ALD膜将沉积在绝缘Al 2 O3膜上，提供第二导电层。第三，将第二绝缘Al 2 O3护套放置在W层上，提供完成的同轴纳米电缆。Al 2 O3/W/Al 2 O3三层中各层的厚度可通过自限制ALD表面化学处理控制在约0.1纳米内。同轴纳米电缆的这种制造已经由提议的研究小组在微克级上进行了演示，并且将使用可扩展的振动/搅拌流化床反应器工艺将其扩大到约10克。新型CNT ALD纳米线或纳米电缆可用作未来纳米级器件、原型电力电缆或“量子线”的构建块。潜在影响远远超出了所提出的纳米电缆/纳米线应用。纳米科学只有在纳米粒子和纳米管的单个表面可以功能化的情况下才能达到真正的“颠覆性”技术地位。纳米颗粒和纳米管的ALD纳米涂层提供了这样的机会。现在可以生产具有设计的电、磁、光、机械、流变或其他特性的纳米颗粒和纳米管。这种功能化纳米颗粒和纳米管的市场包括微电子、国防、硬金属、化妆品、药物输送、高能材料和聚合物/陶瓷纳米复合材料等。

This Small Business Technology Transfer (STTR) Phase I project provides for the commercialization of composite alumina/tungsten/alumina (Al2O3/W/Al2O3) trilayers deposited by Atomic Layer Deposition (ALD) on carbon nanotubes (CNTs) to form coaxial nanowires/nanocables for nanoelectronic applications. Such coaxial nanostructures can be fabricated by first coating CNTs with a conformal and pinhole-free insulating nanolayer of an alumina (Al2O3) sheath to isolate and insulate the nanotubes from their surroundings. Second, a conductive W ALD film will be deposited on the insulating Al2O3 film, providing the second conducting layer. Third, a second insulating Al2O3 sheath is placed over the W layer providing for the completed coaxial nanocable. The thickness of each of the layers in the Al2O3/W/Al2O3 trilayer can be controlled to within approximately 0.1 nanometers by self-limiting ALD surface chemistry processing. This fabrication of a coaxial nanocable has already been demonstrated by the proposing research team at the microgram scale and will be scaled-up to ~ 10 grams using a scalable vibro/stirred fluidized bed reactor process. The novel CNT ALD nanowires or nanocables can be used as building blocks for future nanoscale devices, prototype power cables or "quantum wires".The potential impact extends far beyond this proposed nanocable/nanowire application. Nanoscience will only achieve true "disruptive" technology status if the individual surfaces of nanoparticles and nanotubes can be functionalized. ALD nanocoating of nanoparticles and nanotubes provides such an opportunity. It is now possible to produce nanoparticles and nanotubes with designed electrical, magnetic, optical, mechanical, rheological, or other properties. Markets for such functionalized nanoparticles and nanotubes include microelectronics, defense, hard metals, cosmetics, drug delivery, energetic materials, and polymer/ceramic nanocomposites, among others.