Experimental study and theoretical analysis of the nanometre-scale line structure fabrication by AFM electric lithography

摘要

Bias voltage dependent atomic force microscope (AFM) nanolithography has been widely studied for its potential applications in the fabrication of the nanostructures, nano-electronic devices and nano-electromechanical systems (NEMS). In this work, the fabrication of nanometre-scale line patterns by AFM electric lithography was studied systematically on the conductive graphite sample surface in the ambient conditions. The influences of the determinative process parameters, involving the applied AFM probe tip shape, the bias voltage and the scanning speed, on the fabrication results were sequentially investigated. It was found that the geometric shape of the applied probe tip played an important role in determining the order of magnitude in the material removal rate. While under certain AFM probe tip, the variation of either the voltage amplitude or the scanning speed could result in a transition of the line structure from bulged lines to grooves or vice versa. The theoretical analysis of the underlying mechanisms was also performed.