提出一种"自下而上"的纳米结构的制备方法。在生长有碳纳米管的氧化硅表面沉积数纳米的钯金属膜后,用氢氟酸刻蚀,得到完全由碳纳米管引导的沟槽结构,并且碳纳米管沿沟槽分布在其底部。通过导电原子力显微镜对沟槽内的碳纳米管的表征,发现其仍然具有良好的导电性。在碳纳米管和钯金属膜之间增加一层磁控溅射沉积的氧化硅,可以增加沟槽的深宽比。通过降低钯金属膜的致密程度,沟槽的开口宽度可降至100 nm左右。该方法制备的结构可以进一步用来构建基于碳纳米管的纳电子器件。
The authors present a "bottom-up" method, that is, a palladium film of several nanometers thickness is deposited on the carbon nanotubes (CNTs) grown on a silicon substrate covered by SiO2, then etched in fluorhydric acid solution, the nanometer-sized trenches, which are fully guided by the CNTs located at the bottom of the trenches, are formed. By performing conducting atomic force microscopy measurement, the CNTs inside the trenches were found to have a good electrical conductivity. If an additional silicon oxide layer was predeposited by magnetron sputtering on CNTs before the deposition of palladium film, the aspect ratio of trenches could be increased. By reducing the density of palladium film, the opening width of the trench would be reduced to about 100 nm. This structure with carbon nanotubes embedded in trenches could be further prepared to build nanoelectronic devices based on CNTs.