カーボンナノチューブ探針を用いた高アスペクト比ナノスケール穴加工法の開発

Abstract

Fabrication of a high aspect ratio nanoelectromechanical systems (NEMs) and nanodevices is an indispensable challenge as microelectromechanical systems shrink towards the nanoscale. Here, we focus our attention on a fabrication technique that makes use of the scanning tunneling microscope. Additionally, we tried to establish a fabricating method for a nanoscale pit with a high aspect ratio by using carbon nanotube (CNT) as the probe. The nanostructures produced were Au thin films on mica substrates that were prepared by magnetron sputtering. The results of our experiment show that a threshold value exists for the fabrication of the pits between 1V and 2V. The depth and diameter of the pit increased with the increase in the bias voltage and tunnel current, respectively. Consequently, a bias voltage of 3V and tunnel current of 4 nA were found to be the optimum conditions for a high aspect ratio nanoscale pit fabrication up to 4.5. In changing the fabricating time, depth of the pit increased with the increase in fabricating time, with a little change in the diameter of the pit. This demonstrates that CNT probes can be useful for fabricating structures without changing the diameter of nanoscale CNT probe.