Fabrication of High Aspect Ratio Nanoscale Pit Using Carbon Nanotube Probe

Abstract

ABSTRACTWe developed a method to fabricate nanoscale pits having high aspect ratio, using a scanning tunneling microscope with an attached carbon nanotube (CNT) probe. CNT probes used in this study were synthesized by the pulling method. The nanostructures were produced in Au thin film in an ambient pressure and room temperature. The results of our experiment show that a threshold value exists for the fabrication of the pits between 1 V and 2 V. The depth and diameter of the pit increased with the increase in the bias voltage and tunnel current, respectively. Consequently, a bias voltage of 3 V and tunnel current of 4 nA were found to be the optimum conditions for a high aspect ratio nanoscale pit fabrication. In changing the fabrication time at the optimum conditions, the depth of the pit increased with the increase in the fabrication time, with little change in the diameter of the pit. This demonstrates that CNT probes can be useful for fabricating nanoscale structures.