Department of Electrical and Computer Engineering, University of Cincinnati, Cincinnati, Ohio 45221, USA.
Langmuir. 2010 Jul 20;26(14):11642-7. doi: 10.1021/la101079b.
A self-aligned nanogap between multiple metal layers has been developed using a new controlled undercut and metallization technique (CUMT), and practically applied for self-assembly of individual carbon nanotubes (CNTs) over the developed nanogap. This new method allows conventional optical lithography to fabricate nanogap electrodes and self-aligned patterns with nanoscale precision. The self-aligned nickel (Ni) pattern on the nanogap electrode works as an assembly spot where the residual iron (Fe) catalyst at the end of the CNT is magnetically captured. The captured CNT is forced to be aligned parallel to the flow direction by fluidic shear force. The combined forces of magnetic attraction and fluidic alignment provide massive self-assembly of CNTs at target positions. Both multiwalled nanotubes (MWNTs) and single walled nanotubes (SWNTs) were successfully assembled over the nanogap electrodes, and their electrical characteristics were fully characterized. The CNTs self-assembled on the developed electrodes with a nanogap and showed a very reliable and reproducible current-voltage (I-V) characteristic. The method developed in this work can envisage the mass fabrication of individual CNT-assembled devices which can be applied to nanoelectronic devices or nanobiosensors.
已经开发出了一种使用新的控制刻蚀和金属化技术（CUMT）的多金属层自对准纳米间隙，并将其实际应用于在开发的纳米间隙上自组装单个碳纳米管（CNT）。这种新方法允许传统的光学光刻技术以纳米级精度制造纳米间隙电极和自对准图案。纳米间隙电极上的自对准镍（Ni）图案用作组装点，其中 CNT 末端的残留铁（Fe）催化剂被磁性捕获。捕获的 CNT 被流体剪切力强制平行于流动方向对齐。磁力吸引和流体对准的组合力为 CNT 在目标位置的大规模自组装提供了条件。多壁纳米管（MWNTs）和单壁纳米管（SWNTs）都成功地在纳米间隙电极上组装，并且充分表征了它们的电学特性。在具有纳米间隙的开发电极上自组装的 CNT 表现出非常可靠和可重复的电流-电压（I-V）特性。这项工作中开发的方法可以设想大规模制造单个 CNT 组装器件，这些器件可应用于纳米电子器件或纳米生物传感器。
